| 
                                                29 Oct 2025
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                31 Jul 2025
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                07 May 2025
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                27 Jan 2025
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                25 Oct 2024
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                31 Jul 2024
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                02 May 2024
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Feb 2024
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                10 Nov 2023
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                08 Aug 2023
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                07 May 2023
                                             | 
                                            Audited Results & Final Dividend | 
                                             (Revised)   | 
                                        
                                    
                                        
                                            | 
                                                31 Jan 2023
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                07 Nov 2022
                                             | 
                                            Quarterly Results & Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                10 Aug 2022
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                25 May 2022
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Feb 2022
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                29 Nov 2021
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Nov 2021
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                10 Aug 2021
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Jun 2021
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                05 Mar 2021
                                             | 
                                            Second Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Feb 2021
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Nov 2020
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                02 Sep 2020
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                26 Jun 2020
                                             | 
                                            Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Mar 2020
                                             | 
                                            Interim Dividend | 
                                             (Revised)   | 
                                        
                                    
                                        
                                            | 
                                                06 Mar 2020
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Feb 2020
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Nov 2019
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Aug 2019
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                30 May 2019
                                             | 
                                            Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Mar 2019
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Feb 2019
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                04 Feb 2019
                                             | 
                                            Buy Back of Shares | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                20 Dec 2018
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Nov 2018
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Aug 2018
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                29 May 2018
                                             | 
                                            Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                10 Mar 2018
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                07 Mar 2018
                                             | 
                                            Interim Dividend | 
                                             BM deferred   | 
                                        
                                    
                                        
                                            | 
                                                10 Feb 2018
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Nov 2017
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Aug 2017
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                29 May 2017
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                26 Mar 2017
                                             | 
                                            2nd Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                06 Mar 2017
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Feb 2017
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Dec 2016
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Sep 2016
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                09 Sep 2016
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Jul 2016
                                             | 
                                            Buy Back of Shares | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Jun 2016
                                             | 
                                            Others | 
                                             Approved the buyback of 742750 fully paid equity shares of face value of Rs. 1000/- each (Rupees Thousand only) from the members of the Company on a proportionate basis through tender offer.   | 
                                        
                                    
                                        
                                            | 
                                                11 Jun 2016
                                             | 
                                            Buy-Back of Equity Shares | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                28 May 2016
                                             | 
                                            Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                05 Mar 2016
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                11 Feb 2016
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Nov 2015
                                             | 
                                            Quarterly Results | 
                                             (Revised from 09/11/2015)   | 
                                        
                                    
                                        
                                            | 
                                                12 Aug 2015
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                28 May 2015
                                             | 
                                            Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                27 Feb 2015
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Feb 2015
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                08 Nov 2014
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Aug 2014
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                29 May 2014
                                             | 
                                            Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Feb 2014
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Jan 2014
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Nov 2013
                                             | 
                                            Quarterly Results | 
                                             (Revised)   | 
                                        
                                    
                                        
                                            | 
                                                12 Nov 2013
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                03 Aug 2013
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                27 May 2013
                                             | 
                                            Audited Consolidated Financial Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                20 May 2013
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Mar 2013
                                             | 
                                            Interim Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Feb 2013
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                09 Nov 2012
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                13 Aug 2012
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                28 May 2012
                                             | 
                                            Audited Results (Consolidated) | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                18 May 2012
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Mar 2012
                                             | 
                                            Interim Dividend | 
                                             The Board have approved payment of Interim Dividend for the financial year 2011-12 @ Rs. 9.50/- per share of the thee value of Rs. 10/-.   | 
                                        
                                    
                                        
                                            | 
                                                13 Feb 2012
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                30 Dec 2011
                                             | 
                                            Others | 
                                             The Board has approved switching over of non-coking coal pricing from Useful Heat Value (UHV) based grading system to Gross Caloric Value (GCV) based classification w.e.f. January 01, 2012.   | 
                                        
                                    
                                        
                                            | 
                                                14 Dec 2011
                                             | 
                                            Appointment of Company Secretary | 
                                             For appointment of Shri M. Viswanathan, who possesses the requisite qualification prescribed in the Companies (Appointment and Qualification of Secretary) Rules, 1988 as Company Secretary.   | 
                                        
                                    
                                        
                                            | 
                                                12 Nov 2011
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 Aug 2011
                                             | 
                                            Quarterly Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                25 May 2011
                                             | 
                                            Consolidated Audited Results | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                12 May 2011
                                             | 
                                            Audited Results & Final Dividend | 
                                             -   | 
                                        
                                    
                                        
                                            | 
                                                14 Feb 2011
                                             | 
                                            Quarterly Results & Interim Dividend | 
                                             -   |