Finance and Other Receivables - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans accounted for as troubled debt restructurings	$ 37.9	$ 43.1
TDRs charged-off during the period	1.4	4.8
Repossessed inventory	13.1	25.4
Proceeds from the sales of repossessed assets	$ 58.3	51.7	$ 48.0
Financial Services
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable repayment period	1 year
Financial Services \| Financing Receivable \| Maximum \| Credit Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of portfolio assets	5.00%
Financial Services \| Finance Leases Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Estimated residual values included with finance leases	$ 340.9	$ 239.1

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

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- Definition

Financing receivable repayment period.

+ References

No definition available.

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- Definition

Amount of residual value estimates included with finance leases.

+ References

No definition available.

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- Definition

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+ 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

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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