v3.26.3
Segment Information (Detail) - JPY (¥)
¥ in Millions
 6 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Segment Reporting Information [Line Items]    
Revenues ¥ 1,673,875 ¥ 1,527,599
Interest expense 91,389 85,029
Costs of operating leases 210,824 201,850
Life insurance costs 226,760 220,628
Costs of goods and real estate sold 175,602 154,612
Services expense 318,330 301,699
Selling, general and administrative expenses 401,965 321,039
Total Segment Expenses 1,434,355 1,297,175
Equity in Net income (Loss) of equity method investments and others 809,610 50,327
Segment Profits 239,520 230,424
Other significant non-cash items:    
Depreciation and amortization 217,601 200,584
Increase in policy liabilities and policy account balances 123,224 196,700
Operating leases    
Segment Reporting Information [Line Items]    
Revenues 325,344 309,624
Life insurance premiums and related investment income    
Segment Reporting Information [Line Items]    
Revenues 312,741 299,708
Sales of goods and real estate    
Segment Reporting Information [Line Items]    
Revenues 233,268 206,964
Services income    
Segment Reporting Information [Line Items]    
Revenues 578,915 531,922
Operating Segment    
Segment Reporting Information [Line Items]    
Finance revenues 144,762 138,378
Revenues 1,672,768 1,527,526
Interest expense 82,958 73,423
Costs of operating leases 212,765 203,592
Life insurance costs 226,902 221,076
Costs of goods and real estate sold 174,546 153,383
Services expense 316,411 301,015
Other (income) and expense [1] (1,901) 1,769
Selling, general and administrative expenses 382,823 306,941
Provision for credit losses, and write-downs of long-lived assets and securities 2,564 11,927
Total Segment Expenses 1,397,068 1,273,126
Equity in Net income (Loss) of equity method investments and others 871,689 143,445
Segment Profits 1,147,389 397,845
Other significant non-cash items:    
Depreciation and amortization 215,508 198,310
Increase in policy liabilities and policy account balances 123,224 196,700
Expenditures for long-lived assets 533,628 391,119
Operating Segment | Gains on investment securities and dividends    
Segment Reporting Information [Line Items]    
Revenues 79,383 41,725
Operating Segment | Operating leases    
Segment Reporting Information [Line Items]    
Revenues 327,956 312,413
Operating Segment | Life insurance premiums and related investment income    
Segment Reporting Information [Line Items]    
Revenues 313,593 300,947
Operating Segment | Sales of goods and real estate    
Segment Reporting Information [Line Items]    
Revenues 231,271 204,837
Operating Segment | Services income    
Segment Reporting Information [Line Items]    
Revenues 575,803 529,226
Operating Segment | Japan & APAC    
Segment Reporting Information [Line Items]    
Finance revenues 76,638 76,931
Revenues 610,693 555,548
Interest expense 32,015 26,994
Costs of operating leases 170,597 163,362
Life insurance costs 0 0
Costs of goods and real estate sold 117,658 96,692
Services expense 85,810 62,677
Other (income) and expense [1] 11,155 5,836
Selling, general and administrative expenses 123,381 111,406
Provision for credit losses, and write-downs of long-lived assets and securities 2,273 4,421
Total Segment Expenses 542,889 471,388
Equity in Net income (Loss) of equity method investments and others 848,610 41,545
Segment Profits 916,414 125,705
Other significant non-cash items:    
Depreciation and amortization 152,113 139,552
Increase in policy liabilities and policy account balances 0 0
Expenditures for long-lived assets 237,710 219,972
Operating Segment | Japan & APAC | Gains on investment securities and dividends    
Segment Reporting Information [Line Items]    
Revenues (1,609) 3,041
Operating Segment | Japan & APAC | Operating leases    
Segment Reporting Information [Line Items]    
Revenues 244,028 235,545
Operating Segment | Japan & APAC | Life insurance premiums and related investment income    
Segment Reporting Information [Line Items]    
Revenues 0 0
Operating Segment | Japan & APAC | Sales of goods and real estate    
Segment Reporting Information [Line Items]    
Revenues 161,602 137,210
Operating Segment | Japan & APAC | Services income    
Segment Reporting Information [Line Items]    
Revenues 130,034 102,821
Operating Segment | Infrastructure    
Segment Reporting Information [Line Items]    
Finance revenues 14,807 8,637
Revenues 401,879 452,689
Interest expense 22,005 20,925
Costs of operating leases 39,386 38,933
Life insurance costs 0 0
Costs of goods and real estate sold 55,949 56,424
Services expense 185,390 203,706
Other (income) and expense [1] (3,648) (7,017)
Selling, general and administrative expenses 46,138 43,029
Provision for credit losses, and write-downs of long-lived assets and securities 453 473
Total Segment Expenses 345,673 356,473
Equity in Net income (Loss) of equity method investments and others 25,873 104,792
Segment Profits 82,079 201,008
Other significant non-cash items:    
Depreciation and amortization 42,840 42,481
Increase in policy liabilities and policy account balances 0 0
Expenditures for long-lived assets 219,601 168,945
Operating Segment | Infrastructure | Gains on investment securities and dividends    
Segment Reporting Information [Line Items]    
Revenues (159) 21,446
Operating Segment | Infrastructure | Operating leases    
Segment Reporting Information [Line Items]    
Revenues 81,332 75,830
Operating Segment | Infrastructure | Life insurance premiums and related investment income    
Segment Reporting Information [Line Items]    
Revenues 0 0
Operating Segment | Infrastructure | Sales of goods and real estate    
Segment Reporting Information [Line Items]    
Revenues 68,041 67,052
Operating Segment | Infrastructure | Services income    
Segment Reporting Information [Line Items]    
Revenues 237,858 279,724
Operating Segment | USA & Europe    
Segment Reporting Information [Line Items]    
Finance revenues 53,243 52,738
Revenues 346,529 218,270
Interest expense 28,684 25,245
Costs of operating leases 2,782 1,297
Life insurance costs 0 0
Costs of goods and real estate sold 939 267
Services expense 45,211 34,632
Other (income) and expense [1] (9,409) 2,953
Selling, general and administrative expenses 183,958 123,649
Provision for credit losses, and write-downs of long-lived assets and securities (241) 7,059
Total Segment Expenses 251,924 195,102
Equity in Net income (Loss) of equity method investments and others (2,794) (2,892)
Segment Profits 91,811 20,276
Other significant non-cash items:    
Depreciation and amortization 6,642 4,082
Increase in policy liabilities and policy account balances 0 0
Expenditures for long-lived assets 76,062 2,100
Operating Segment | USA & Europe | Gains on investment securities and dividends    
Segment Reporting Information [Line Items]    
Revenues 81,151 17,238
Operating Segment | USA & Europe | Operating leases    
Segment Reporting Information [Line Items]    
Revenues 2,596 1,038
Operating Segment | USA & Europe | Life insurance premiums and related investment income    
Segment Reporting Information [Line Items]    
Revenues 0 0
Operating Segment | USA & Europe | Sales of goods and real estate    
Segment Reporting Information [Line Items]    
Revenues 1,628 575
Operating Segment | USA & Europe | Services income    
Segment Reporting Information [Line Items]    
Revenues 207,911 146,681
Operating Segment | Insurance    
Segment Reporting Information [Line Items]    
Finance revenues 74 72
Revenues 313,667 301,019
Interest expense 254 259
Costs of operating leases 0 0
Life insurance costs 226,902 221,076
Costs of goods and real estate sold 0 0
Services expense 0 0
Other (income) and expense [1] 1 (3)
Selling, general and administrative expenses 29,346 28,857
Provision for credit losses, and write-downs of long-lived assets and securities 79 (26)
Total Segment Expenses 256,582 250,163
Equity in Net income (Loss) of equity method investments and others 0 0
Segment Profits 57,085 50,856
Other significant non-cash items:    
Depreciation and amortization 13,913 12,195
Increase in policy liabilities and policy account balances 123,224 196,700
Expenditures for long-lived assets 255 102
Operating Segment | Insurance | Gains on investment securities and dividends    
Segment Reporting Information [Line Items]    
Revenues 0 0
Operating Segment | Insurance | Operating leases    
Segment Reporting Information [Line Items]    
Revenues 0 0
Operating Segment | Insurance | Life insurance premiums and related investment income    
Segment Reporting Information [Line Items]    
Revenues 313,593 300,947
Operating Segment | Insurance | Sales of goods and real estate    
Segment Reporting Information [Line Items]    
Revenues 0 0
Operating Segment | Insurance | Services income    
Segment Reporting Information [Line Items]    
Revenues ¥ 0 ¥ 0
[1] “Other (income) and expense” includes items such as expenses of taxes and insurance premiums related to finance leases, impairment of goodwill and intangible assets, gains and losses on derivatives, and foreign exchange gains and losses.