v3.25.2
Accumulated other comprehensive income - Changes in Accumulated Other Comprehensive Income After Tax (Detail)
₨ in Millions, $ in Millions
 12 Months Ended
Mar. 31, 2025
INR (₨)
Mar. 31, 2025
USD ($)
Mar. 31, 2024
INR (₨)
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Balance ₨ 7,886,182.8   ₨ 2,917,837.9
Net unrealized gain/ (loss) arising during the period 147,594.0   78,846.4
Amounts reclassified to income 9,835.5   4,856.3
Long-duration insurance contract discount rate change (59,827.6)   (34,112.6)
Transferred to undistributed policyholders earnings account 16,525.9   3,391.4
Less: Other comprehensive income attributable to shareholders of noncontrolling interest 1,393.3   248.2
Balance 8,622,891.0 $ 100,935.2 7,886,182.8
AFS debt Securities      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Balance (7,505.2)   (74,923.1)
Net unrealized gain/ (loss) arising during the period 145,589.7   78,036.1
Amounts reclassified to income 9,835.5   4,856.3
Long-duration insurance contract discount rate change 0.0   0.0
Transferred to undistributed policyholders earnings account (58,778.7)   0.0
Less: Other comprehensive income attributable to shareholders of noncontrolling interest 1,361.3   15,474.5
Balance 87,780.0 1,027.5 (7,505.2)
Foreign Currency Translation Reserve      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Balance 7,441.8   6,649.4
Net unrealized gain/ (loss) arising during the period 2,004.3   810.3
Amounts reclassified to income 0.0   0.0
Long-duration insurance contract discount rate change 0.0   0.0
Transferred to undistributed policyholders earnings account 0.0   0.0
Less: Other comprehensive income attributable to shareholders of noncontrolling interest 32.0   17.9
Balance 9,414.1 110.2 7,441.8
Long-Duration Insurance Contract      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Balance (15,477.0)   0.0
Net unrealized gain/ (loss) arising during the period 0.0   0.0
Amounts reclassified to income 0.0   0.0
Long-duration insurance contract discount rate change (59,827.6)   (34,112.6)
Transferred to undistributed policyholders earnings account 75,304.6   3,391.4
Less: Other comprehensive income attributable to shareholders of noncontrolling interest 0.0   (15,244.2)
Balance 0.0 0.0 (15,477.0)
Accumulated Other Comprehensive Income (Loss)      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Balance (15,540.4)   (68,273.7)
Balance ₨ 97,194.1 $ 1,137.7 ₨ (15,540.4)