Investment in Operating Leases (Investment in Operating Leases) (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2020	Mar. 31, 2019
Schedule of Operating Leases [Line Items]
Investment in Operating Leases	¥ 1,400,001	¥ 1,335,959
Investment in Operating Leases
Schedule of Operating Leases [Line Items]
Property Subject to or Available for Operating Lease, Gross	1,931,309	1,938,515
Accumulated depreciation	(678,245)	(634,478)
Net	1,253,064	1,304,037
Accrued rental receivables	25,384	31,922
Investment in Operating Leases	1,400,001	1,335,959
Transportation equipment \| Investment in Operating Leases
Schedule of Operating Leases [Line Items]
Property Subject to or Available for Operating Lease, Gross	1,305,908	1,304,925
Measuring and information-related equipment \| Investment in Operating Leases
Schedule of Operating Leases [Line Items]
Property Subject to or Available for Operating Lease, Gross	287,301	266,436
Real Estate Asset \| Investment in Operating Leases
Schedule of Operating Leases [Line Items]
Property Subject to or Available for Operating Lease, Gross	305,981	336,002
Other \| Investment in Operating Leases
Schedule of Operating Leases [Line Items]
Property Subject to or Available for Operating Lease, Gross	¥ 32,119	¥ 31,152

Operating Leases Accrued Rental Receivable

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- Definition

Property Subject to or Available for Operating Lease, Net of Accumulated Depreciation

+ References

No definition available.

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- Definition

Schedule of Operating Leases [Line Items]

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- Definition

The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41460-112716

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- Definition

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

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