Finance and Other Receivables - Additional Information (Detail) - Financial Services - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, 90 days past due and still accruing	$ 0.0		$ 0.0
Months contractual terms extended	4 months		4 months
Loans accounted for as troubled debt restructurings	$ 40.6		$ 43.1
TDRs charged-off during the period	1.5	$ 5.1
Repossessed inventory	20.4		$ 25.4
Proceeds from the sales of repossessed assets	$ 44.7	$ 34.2
Loans And Leases \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contractual terms of retails loans and finance leases	36 months
Loans And Leases \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contractual terms of retails loans and finance leases	60 months
Financing Receivable \| Maximum \| Credit Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of portfolio assets	5.00%

Percentage of single customer or dealer balances of total portfolio receivables.

No definition available.

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- Definition

Contractual term extensions (months) for modified finance receivables.

+ References

No definition available.

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- Definition

Contractual terms of retails loans and finance leases.

+ References

No definition available.

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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 the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

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- Definition

Carrying amount as of the balance sheet date of assets other than real property that were received in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522

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- Definition

The cash inflow from the sale assets received in full or partial satisfaction of a receivable including real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts. Foreclosed assets also include loans that are treated as if the underlying collateral had been foreclosed because the institution has taken possession of the collateral, even though legal foreclosure or repossession proceedings have not taken place.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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