Investment in Operating Leases - Schedule of Investment in Operating Leases (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Leases [Abstract]
Operating lease vehicles	$ 33,861	$ 30,288
Accumulated depreciation	(5,678)	(5,070)
Deferred dealer participation and IDC	109	98
Unearned subsidy income	(1,016)	(819)
Estimated early termination losses	(56)	(58)
Total investment in operating leases	$ 27,220	$ 24,439	$ 23,917

Accrued early termination losses related to operating leases based on estimated lessee defaults.

No definition available.

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- Definition

Subsidy payments received from the Parent companies, which supplement the revenues on financing products offered under incentive programs. Subsidy payments received on leases are deferred and recognized as revenue over the term of the related contracts. The unearned balance is recognized as reductions to the carrying value of investment in operating leases.

+ References

No definition available.

+ Details

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- Definition

This element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This element is net of accumulated amortization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=6748888&loc=d3e40246-112709

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6453741&loc=d3e40879-112712

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=6748888&loc=d3e40588-112709

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- References

No definition available.

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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

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-URI http://asc.fasb.org/extlink&oid=6453916&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41457-112716

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-Publisher FASB
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-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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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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