v3.26.1
Mizuho Financial Group, Inc., Parent Company (Condensed Statements of Income) (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Income:      
Total [1] ¥ 8,794,500 ¥ 8,169,900 ¥ 8,510,700
Expenses:      
Equity in undistributed net income of subsidiaries and affiliated companies—net [2] 75,152 28,233 19,791
Income tax expense (benefit) 359,613 199,532 425,120
Net income attributable to MHFG shareholders 1,158,031 593,393 912,473
Parent Company      
Income:      
Management fees from subsidiaries 58,247 56,745 51,770
Other income 29,805 13,579 4,444
Total 977,522 877,154 847,800
Expenses:      
Operating expenses 69,651 65,673 60,037
Interest expense 318,464 267,294 230,780
Other expense 3,457 4,076 11,286
Total 391,572 337,043 302,103
Equity in undistributed net income of subsidiaries and affiliated companies—net 567,966 53,548 365,266
Income before income tax expense (benefit) 1,153,917 593,660 910,964
Income tax expense (benefit) (4,114) 267 (1,509)
Net income attributable to MHFG shareholders 1,158,031 593,393 912,473
Parent Company | Related Party      
Income:      
Interest income on loans and discounts 319,574 269,329 232,272
Parent Company | Banking Subsidiaries      
Income:      
Banking subsidiaries 538,058 527,035 547,487
Parent Company | Non-banking subsidiaries and affiliated companies      
Income:      
Banking subsidiaries ¥ 31,838 ¥ 10,466 ¥ 11,826
[1] Total revenue is comprised of Interest and dividend income and Noninterest income.    
[2] These amounts are revenues from contracts that do not meet the scope of ASC 606.