Equipment on Operating Leases for Truck and Other Segment and for Financial Services Segment (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property Subject to or Available for Operating Lease [Line Items]
Total	$ 3,240.5	$ 3,328.4	$ 2,888.7
Truck, Parts and Other
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases	1,222.9	1,357.8
Less allowance for depreciation	(288.4)	(319.5)
Total	934.5	1,038.3
Financial Services
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases	3,269.0	3,212.2
Less allowance for depreciation	(963.0)	(922.1)
Total	$ 2,306.0	$ 2,290.1

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

Reference 1: 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

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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

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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

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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