v3.26.1
Discontinued operations - Summary of Results of Operations from Discontinued Operations (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Disclosure Of Results Of Operations From Discontinued Operations [Line Items]      
Net income (loss) from discontinued operations ¥ (1,357,758) ¥ 74,169 ¥ 124,513
Comprehensive income from discontinued operations 51,006 (41,173) (17,166)
Discontinued operations [member]      
Disclosure Of Results Of Operations From Discontinued Operations [Line Items]      
Financial services revenue 678,023 922,147 1,760,731
Financial services expenses 640,811 789,702 1,606,370
Reclassification of accumulated other comprehensive income related to the disposal group to net income (loss) (1,377,795)    
Other income (expenses), net (6,450) (1,917) 19,215
Income (loss) before income taxes from discontinued operations (1,347,033) 130,528 173,576
Income taxes 10,725 56,359 49,063
Net income (loss) from discontinued operations (1,357,758) 74,169 124,513
Other comprehensive income, net of tax, from discontinued operations 1,408,764 (115,342) (141,679)
Changes in equity instruments measured at fair value through other comprehensive income 963 (998) 1,013
Remeasurement of defined benefit pension plans (106) (444) (1,169)
Changes in debt instruments measured at fair value through other comprehensive income 1,346,457 (681,515) (704,636)
Insurance finance income (expenses) 60,684 568,291 563,396
Others 766 (676) (283)
Comprehensive income from discontinued operations ¥ 51,006 ¥ (41,173) ¥ (17,166)