v3.26.1
Segment Information (Reconciliation of Segment Totals to Consolidated Financial Statement Amounts) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Segment revenues:      
Revenues ¥ 3,330,831 ¥ 2,874,821 ¥ 2,814,361
Segment profits:      
Total segment profits 456,248 331,826 360,713
Net income attributable to the noncontrolling interests and net income attributable to the redeemable noncontrolling interests 758 (394) (137)
Income before Income Taxes 691,431 480,463 469,975
Segment assets:      
Assets 18,002,776 16,866,251 16,322,100
Operating Segment      
Segment revenues:      
Revenues 3,326,146 2,871,405 2,804,921
Segment profits:      
Total segment profits 732,597 544,668 561,521
Segment assets:      
Assets 17,435,466 16,456,627 16,022,129
Corporate, Non-Segment      
Segment revenues:      
Revenues 84,865 64,628 64,922
Segment profits:      
Corporate losses (52,821) (64,475) (84,644)
Net income attributable to the noncontrolling interests and net income attributable to the redeemable noncontrolling interests 11,655 270 (6,902)
Segment assets:      
Assets 2,956,157 2,494,395 2,307,313
Intersegment Eliminations      
Segment revenues:      
Revenues (80,180) (61,212) (55,482)
Segment assets:      
Assets ¥ (2,388,847) ¥ (2,084,771) ¥ (2,007,342)