v3.26.1
Intangible Assets - Changes in Other Intangible Assets (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance ¥ 803,680 ¥ 720,984  
Additions 331,201 264,975  
Acquisition of subsidiaries and businesses 3,850  
Disposals (78,098) (2,155)  
Amortization (200,273) (198,030)  
Impairment losses (2,389) (1,551) ¥ (9,648)
Exchange differences 6,829 (2,853)  
Others 52,569 22,310  
Carrying amount ending balance 917,369 803,680 720,984
Gross carrying amount [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 2,051,330 1,955,253  
Carrying amount ending balance 1,863,383 2,051,330 1,955,253
Accumulated depreciation, amortisation and impairment [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance (1,247,650) (1,234,269)  
Carrying amount ending balance (946,014) (1,247,650) (1,234,269)
Software [member] | Internally generated [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 489,691 410,651  
Additions 242,226 176,356  
Acquisition of subsidiaries and businesses  
Disposals (72,891) (401)  
Amortization (112,194) (106,173)  
Impairment losses (1,247) (250)  
Exchange differences 1,426 (72)  
Others 847 9,580  
Carrying amount ending balance 547,858 489,691 410,651
Software [member] | Internally generated [member] | Gross carrying amount [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 1,078,808 967,957  
Carrying amount ending balance 982,259 1,078,808 967,957
Software [member] | Internally generated [member] | Accumulated depreciation, amortisation and impairment [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance (589,117) (557,306)  
Carrying amount ending balance (434,401) (589,117) (557,306)
Software [member] | Purchased [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 242,058 212,616  
Additions 86,490 77,450  
Acquisition of subsidiaries and businesses 3,218  
Disposals (1,496) (1,752)  
Amortization (72,930) (64,853)  
Impairment losses (1,141) (1,239)  
Exchange differences 4,484 (1,071)  
Others 53,607 20,907  
Carrying amount ending balance 314,290 242,058 212,616
Software [member] | Purchased [member] | Gross carrying amount [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 664,363 659,496  
Carrying amount ending balance 662,508 664,363 659,496
Software [member] | Purchased [member] | Accumulated depreciation, amortisation and impairment [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance (422,305) (446,880)  
Carrying amount ending balance (348,218) (422,305) (446,880)
Contractual customer relationships [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 23,704 34,347  
Additions  
Acquisition of subsidiaries and businesses  
Disposals  
Amortization (5,439) (10,462)  
Impairment losses  
Exchange differences 335 (761)  
Others 580  
Carrying amount ending balance 18,600 23,704 34,347
Contractual customer relationships [member] | Gross carrying amount [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 80,541 177,361  
Carrying amount ending balance 81,007 80,541 177,361
Contractual customer relationships [member] | Accumulated depreciation, amortisation and impairment [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance (56,837) (143,014)  
Carrying amount ending balance (62,407) (56,837) (143,014)
Trademarks [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 2,385  
Additions  
Acquisition of subsidiaries and businesses  
Disposals  
Amortization (547) (541)  
Impairment losses  
Exchange differences 88 (162)  
Others 3,088  
Carrying amount ending balance 1,926 2,385
Trademarks [member] | Gross carrying amount [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 44,754 41,828  
Carrying amount ending balance 44,884 44,754 41,828
Trademarks [member] | Accumulated depreciation, amortisation and impairment [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance (42,369) (41,828)  
Carrying amount ending balance (42,958) (42,369) (41,828)
Other intangibles [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 45,842 63,370  
Additions 2,485 11,169  
Acquisition of subsidiaries and businesses 632  
Disposals (3,711) (2)  
Amortization (9,163) (16,001)  
Impairment losses (1) (62)  
Exchange differences 496 (787)  
Others (1,885) (11,845)  
Carrying amount ending balance 34,695 45,842 63,370
Other intangibles [member] | Gross carrying amount [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance 182,864 108,611  
Carrying amount ending balance 92,725 182,864 108,611
Other intangibles [member] | Accumulated depreciation, amortisation and impairment [member]      
Disclosure of detailed information about intangible assets [line items]      
Carrying amount beginning balance (137,022) (45,241)  
Carrying amount ending balance ¥ (58,030) ¥ (137,022) ¥ (45,241)