Pension Plans (Fair Value of Pension Plan Assets by Asset Category) (Detail) - JPY (¥) ¥ in Millions		Mar. 31, 2022		Mar. 31, 2021		Mar. 31, 2020
Japan
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		¥ 137,317		¥ 134,392		¥ 122,780
Japan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Japan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		34,034		33,825
Japan | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Japan | Defined Benefit Plan, Equity Securities | Japan Pooled Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		16,002	[1]	17,823	[2]
Japan | Defined Benefit Plan, Equity Securities | Japan Pooled Funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0	[1]	0	[2]
Japan | Defined Benefit Plan, Equity Securities | Japan Pooled Funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0	[1]	0	[2]
Japan | Defined Benefit Plan, Equity Securities | Japan Pooled Funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0	[1]	0	[2]
Japan | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	21,366		22,231
Japan | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	0		0
Japan | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	0		0
Japan | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	0		0
Japan | Defined Benefit Plan, Debt Security | Japan Pooled Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		27,845	[4]	24,127	[5]
Japan | Defined Benefit Plan, Debt Security | Japan Pooled Funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0	[4]	0	[5]
Japan | Defined Benefit Plan, Debt Security | Japan Pooled Funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0	[4]	0	[5]
Japan | Defined Benefit Plan, Debt Security | Japan Pooled Funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0	[4]	0	[5]
Japan | Defined Benefit Plan, Debt Security | Other than Japan Pooled Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[6]	38,070		36,386
Japan | Defined Benefit Plan, Debt Security | Other than Japan Pooled Funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[6]	0		0
Japan | Defined Benefit Plan, Debt Security | Other than Japan Pooled Funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[6]	0		0
Japan | Defined Benefit Plan, Debt Security | Other than Japan Pooled Funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[6]	0		0
Japan | Other Plan Asset | Life Insurance Company General Accounts
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	29,462		28,977
Japan | Other Plan Asset | Life Insurance Company General Accounts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	0		0
Japan | Other Plan Asset | Life Insurance Company General Accounts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	29,462		28,977
Japan | Other Plan Asset | Life Insurance Company General Accounts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	0		0
Japan | Other Plan Asset | Other Investment
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	4,572		4,848
Japan | Other Plan Asset | Other Investment | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	0		0
Japan | Other Plan Asset | Other Investment | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	4,572		4,848
Japan | Other Plan Asset | Other Investment | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	0		0
Overseas plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		127,251		119,858		¥ 96,994
Overseas plans | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		115,931		110,728
Overseas plans | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		10,289		8,513
Overseas plans | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Shares
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		59,932		58,483
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Shares | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		59,932		58,483
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Shares | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Shares | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	1,031		617
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	0		0
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	0		0
Overseas plans | Defined Benefit Plan, Equity Securities | Other than Japan Pooled Funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[3]	0		0
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Government Bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		55,999		52,245
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Government Bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		55,999		52,245
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Government Bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Government Bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Municipal Bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		4,411		4,589
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Municipal Bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Municipal Bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		4,411		4,589
Overseas plans | Defined Benefit Plan, Debt Security | Other than Japan Municipal Bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		0		0
Overseas plans | Other Plan Asset | Life Insurance Company General Accounts
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	351		325
Overseas plans | Other Plan Asset | Life Insurance Company General Accounts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	0		0
Overseas plans | Other Plan Asset | Life Insurance Company General Accounts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	351		325
Overseas plans | Other Plan Asset | Life Insurance Company General Accounts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[7]	0		0
Overseas plans | Other Plan Asset | Other Investment
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	5,527		3,599
Overseas plans | Other Plan Asset | Other Investment | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	0		0
Overseas plans | Other Plan Asset | Other Investment | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	5,527		3,599
Overseas plans | Other Plan Asset | Other Investment | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	[8]	¥ 0		¥ 0

[1] These funds invest in listed shares including shares of ORIX Corporation in the amounts of ¥22 million at March 31, 2022.

[2] These funds invest in listed shares including shares of ORIX Corporation in the amounts of ¥22 million at March 31, 2021.

[3] These funds invest in listed shares.

[4] These funds invest approximately 70% in Japanese government bonds, and approximately 30% in Japanese corporate bonds. These funds include corporate bonds of ORIX Corporation in the amounts of ¥37 million at March 31, 2022.

[5] These funds invest approximately 70% in Japanese government bonds, approximately 10% in Japanese municipal bonds, and approximately 20% in Japanese corporate bonds. These funds include corporate bonds of ORIX Corporation in the amounts of ¥51 million at March 31, 2021.

[6] These funds invest approximately 90% in foreign government bonds and approximately 10% in foreign corporate bonds.

[7] Life insurance company general accounts are accounts with guaranteed capital and minimum interest rate, in which life insurance companies manage funds on several contracts.

[8] Others include derivative instruments held for hedging change in the fair value of equity securities, and short-term instruments.