XML 165 R153.htm IDEA: XBRL DOCUMENT v3.8.0.1
Commitments and Contingencies - Additional Information (Detail)
$ in Millions
 12 Months Ended
Mar. 31, 2018
INR (₨)
Mar. 31, 2017
INR (₨)
Mar. 31, 2016
INR (₨)
Jan. 31, 2018
INR (₨)
Dec. 31, 2017
INR (₨)
Dec. 31, 2017
USD ($)
Nov. 30, 2017
INR (₨)
Mar. 31, 2011
INR (₨)
Disclosure of contingent liabilities [line items]                
Rental payments under lease agreement ₨ 6,236,000,000 ₨ 5,953,000,000 ₨ 5,184,000,000          
Operating lease agreements term 15 years              
Capital commitments ₨ 13,091,000,000 12,238,000,000            
Financial guarantee amount 21,546,000,000 22,023,000,000            
Tax contingent liability [member]                
Disclosure of contingent liabilities [line items]                
Contingent tax liability 101,440,000,000 89,623,000,000         ₨ 3,286,000,000 ₨ 47,583,000,000
Interest on contingent tax liability             ₨ 1,166,000,000 ₨ 13,832,000,000
Contingent liability     0          
Tax contingent liability [member] | Dispute resolution panel [member]                
Disclosure of contingent liabilities [line items]                
Contingent tax liability     4,241,000,000 ₨ 8,701,000,000        
Interest on contingent tax liability     ₨ 1,376,000,000 ₨ 2,700,000,000        
Excise duty, Custom duty, sales tax and other matters [member]                
Disclosure of contingent liabilities [line items]                
Contingent tax liability ₨ 7,745,000,000 ₨ 7,242,000,000            
Legal proceedings contingent liability [member]                
Disclosure of contingent liabilities [line items]                
Contingent liability         ₨ 9,124,000,000 $ 140