Summary of Long-Term Debt (Parenthetical) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Obligations under capitalized leases	$ 24,913
Term Loan A
Debt Instrument [Line Items]
Unamortized discount	$ 1,593	$ 2,035
3.750% Senior Secured Notes due 2019
Debt Instrument [Line Items]
Debt instruments, maturity date	2019
Unamortized discount	$ 155	198
Senior notes, interest rate	3.75%
4.750% Senior Secured Notes due 2022
Debt Instrument [Line Items]
Debt instruments, maturity date	2022
Unamortized discount	$ 177	204
Senior notes, interest rate	4.75%
7.125% Senior Secured Notes due 2016
Debt Instrument [Line Items]
Debt instruments, maturity date	2016
Senior notes, interest rate	7.125%
Unamortized net premium	$ 4	7
Notes Payable And Mortgages Payable
Debt Instrument [Line Items]
Obligations under capitalized leases	$ 24,900	$ 21,600
Weighted average interest	6.80%	6.40%
Term Loans With Varying Maturities
Debt Instrument [Line Items]
Debt instruments, maturity date	2027
Revenue Bonds
Debt Instrument [Line Items]
Interest at floating rates		0.05%

Debt instruments maturity date.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 7

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- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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 debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- Definition

The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

No definition available.

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