Leases - Lessor: Investment in Operating Leases (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2020	Mar. 31, 2019
Property Subject to or Available for Operating Lease [Line Items]
Right-of-use-asset (operating leases)	¥ 270,160
Investment in Operating Leases	1,400,001	¥ 1,335,959
Investment in Operating Leases
Property Subject to or Available for Operating Lease [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
Right-of-use-asset (operating leases)	121,553
Accrued rental receivables	25,384	31,922
Investment in Operating Leases	1,400,001	1,335,959
Transportation equipment \| Investment in Operating Leases
Property Subject to or Available for Operating Lease [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
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	287,301	266,436
Real Estate Asset \| Investment in Operating Leases
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	305,981	336,002
Other \| Investment in Operating Leases
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	¥ 32,119	¥ 31,152

Operating Leases Accrued Rental Receivable

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

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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
-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
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-Topic 840
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41457-112716

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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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