v3.26.1
Other comprehensive income (loss) - Changes in Accumulated other comprehensive income (loss) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Accumulated other comprehensive income (loss) [Line Items]      
Balance at beginning of year ¥ 447,808 ¥ 459,984 ¥ 318,454
Other comprehensive income (loss) before reclassifications 100,497 (15,081) 140,917
Reclassifications out of accumulated other comprehensive income (loss) (84) 2,905 613
Net change during the year 100,413 (12,176) 141,530
Balance at end of year 548,221 447,808 459,984
Cumulative translation adjustments [Member]      
Accumulated other comprehensive income (loss) [Line Items]      
Balance at beginning of year 407,977 444,071 242,767
Other comprehensive income (loss) before reclassifications 142,536 (38,121) 201,662
Reclassifications out of accumulated other comprehensive income (loss) (12) 2,027 (358)
Net change during the year 142,524 (36,094) 201,304
Balance at end of year 550,501 407,977 444,071
Pension liability adjustment [Member]      
Accumulated other comprehensive income (loss) [Line Items]      
Balance at beginning of year [1] (7,105) (19,512) (32,174)
Other comprehensive income (loss) before reclassifications [1] 6,062 11,317 11,220
Reclassifications out of accumulated other comprehensive income (loss) [1] 921 1,090 1,442
Net change during the year [1] 6,983 12,407 12,662
Balance at end of year [1] (122) (7,105) (19,512)
Net unrealized gain (loss) on non-trading debt securities [Member]      
Accumulated other comprehensive income (loss) [Line Items]      
Balance at beginning of year [2] (1,147)  
Other comprehensive income (loss) before reclassifications [2] (2,215) (1,147)  
Reclassifications out of accumulated other comprehensive income (loss) [2]  
Net change during the year [2] (2,215) (1,147)  
Balance at end of year [2] (3,362) (1,147)
Own credit adjustments [Member]      
Accumulated other comprehensive income (loss) [Line Items]      
Balance at beginning of year [3] 48,083 35,425 107,861
Other comprehensive income (loss) before reclassifications [3] (45,886) 12,870 (71,965)
Reclassifications out of accumulated other comprehensive income (loss) [3] (993) (212) (471)
Net change during the year [3] (46,879) 12,658 (72,436)
Balance at end of year [3] ¥ 1,204 ¥ 48,083 ¥ 35,425
[1] See Note 15“Employee benefit plans” for further information.
[2] See Note 6 “Non-trading investments” for further information.
[3] See Note 2 “Fair value measurements” for further information.