Long-Term Obligations - Securitization Facility - Additional Information (Detail) - Accounts Receivable Securitization Facility [Member] - 2018 [Member] - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Interest rate margins	1.35%
Commitment fees on unused portion of available commitments	0.25%
Commitment fee description	The Securitization Facility provides a LIBOR spread on borrowings of 1.35% and for an unused commitment fee of 0.45% at any time the average daily borrowings during the month were less than 25% of the average daily available funding during such month and 0.25% at all other times.
Secured debt		$ 185,000,000
Amendment 2015 [Member]
Debt Instrument [Line Items]
Securitized facility amended date	Feb. 25, 2015
Highest balance outstanding	$ 185,000,000	185,000,000
Secured debt		$ 185,000,000
Minimum [Member] \| Amendment 2015 [Member]
Debt Instrument [Line Items]
Estimated Finance receivable	100,000,000
Maximum [Member] \| Amendment 2015 [Member]
Debt Instrument [Line Items]
Estimated Finance receivable	$ 130,000,000
LIBOR Rate [Member] \| Subject To Average Daily Borrowings [Member]
Debt Instrument [Line Items]
Commitment fees on unused portion of available commitments	0.45%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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.

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- Definition

Description of the fees for amounts available, but unused under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Maximum amount borrowed under the credit facility at any time during the period.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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Estimated finance receivable.

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Loans and leases modification date amendment.

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