v3.26.1
Deferred Income Tax - Changes of Net Deferred Tax Assets and Liabilities (Detail) - JPY (¥)
¥ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Changes in Deferred Tax Assets and Liabilities [Line Items]      
Deferred tax benefit ¥ 152,515 ¥ 310,959 ¥ 56,011
IFRS 9 [member]      
Changes in Deferred Tax Assets and Liabilities [Line Items]      
At beginning of period (202,591) (622,259)  
Deferred tax benefit 152,515 310,959  
Deferred tax relating to other comprehensive income:      
Remeasurements of defined benefit plans reserve (30,563) 8,168  
Financial instruments at fair value through other comprehensive income reserve (121,432) 103,410  
Own credit on financial liabilities designated at fair value through profit or loss reserve (200) (3,013)  
Exchange differences on translating foreign operations reserve (20)  
Acquisition and disposal of subsidiaries and businesses 524 (314)  
Exchange differences and others (1,650) 478  
At end of period ¥ (203,397) ¥ (202,591) ¥ (622,259)