Components of Finance Receivables (Detail) (JPY ¥) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Leases Disclosure [Line Items]
Total minimum lease payments receivable	¥ 204,326	¥ 215,925
Unguaranteed residual values	8,195	11,120
Executory costs	(2,275)	(2,063)
Unearned income	(24,955)	(27,891)
Financing Receivable, Gross , Total	185,291	197,091
Less allowance for doubtful receivables	(7,039)	(7,983)	(9,023)
Capital Leases, Net Investment in Direct Financing and Sales Type Leases, Total	178,252	189,108
Less current portion	(66,337)	(71,500)
Capital Leases, Lessor Balance Sheet, Net Investment in Direct Financing and Sales Type Leases, Noncurrent, Total	¥ 111,915	¥ 117,608

Capital Leases, Net Investment in Sales Type Leases and Direct Financing Leases, Executory Costs

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- Definition

Capital Leases, Net Investment in Sales Type Leases and Direct Financing Leases, Unearned Income

+ References

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- Definition

Capital Leases, Net Investment in Sales Type Leases and Direct Financing Leases, Unguaranteed Residual Values

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- Definition

Financing Receivable, Gross

+ References

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- Definition

Future minimum lease rental payments receivable for the five years following the balance sheet date and the future minimum payment amount in total on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph a(i)(a)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (b)

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- Definition

The net amount due within one year of the balance sheet date or the normal operating cycle, if longer, consisting of: (a) minimum lease payments due on direct financing and sales-type leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs on direct financing leases; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph a(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6952072&loc=d3e45377-112738

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- Definition

The net amount due after one year of the balance sheet date or beyond the normal operating cycle, if longer, consisting of: (a) minimum lease payments due on direct financing and sales-type leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs on direct financing leases; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph a(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6952072&loc=d3e45377-112738

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- Definition

The lessor's asset under sales type and direct financing leases. The net investment in direct financing and sales-type leases as of the balance sheet date consisting of: (a) minimum lease payments due on direct financing leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs on direct financing leases; less: (i) estimated executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph a(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6952072&loc=d3e45377-112738

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (c)(1)

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