Summary of Long-Term Debt (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Notes Payable And Mortgages Payable
Debt Instrument [Line Items]
Obligations under capitalized leases	21,600	6,633
Weighted average interest	6.40%	5.90%
Term Loans With Varying Maturities
Debt Instrument [Line Items]
Debt instruments, maturity date	2037
Term Loan A
Debt Instrument [Line Items]
Unamortized discount	2,035	3,340
Term Loan B Facility
Debt Instrument [Line Items]
Unamortized discount	0	6,473
Revenue Bonds
Debt Instrument [Line Items]
Interest at floating rates	0.05%	0.10%
Debt instruments, maturity date	2015
3.750% Senior Secured Notes due 2019
Debt Instrument [Line Items]
Debt instruments, maturity date	2019
Senior notes, interest rate	3.75%
Unamortized discount	198
4.750% Senior Secured Notes due 2022
Debt Instrument [Line Items]
Debt instruments, maturity date	2022
Senior notes, interest rate	4.75%
Unamortized discount	204
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	7	11
7.00% Senior Unsecured Notes due 2018
Debt Instrument [Line Items]
Debt instruments, maturity date	2018
Senior notes, interest rate	7.00%

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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: 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

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- Definition

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

+ References

No definition available.

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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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: 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))

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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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

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-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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