Investment in Operating Leases (Detail) - Entity [Domain] - JPY (¥) ¥ in Millions	Mar. 31, 2015	Mar. 31, 2014
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	¥ 1,781,507	¥ 1,808,888
Accumulated depreciation	(506,801)	(449,435)
Net	1,274,706	1,359,453
Accrued rental receivables	21,514	20,288
Investment in Operating Leases	1,296,220	1,379,741
Transportation equipment
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	934,430	845,820
Measuring and information-related equipment
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	236,922	228,386
Real Estate
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	590,388	716,883
Other
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	¥ 19,767	¥ 17,799

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

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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41460-112716

+ Details

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Period Type:	instant

- 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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41457-112716

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

+ Details

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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.

+ Details

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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

+ Details

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- Details

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- Details

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