LINES OF CREDIT AND LONG-TERM DEBT - Outstanding Lines of Credit and Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Total debt outstanding	$ 1,047,177us-gaap_DebtAndCapitalLeaseObligations	$ 984,787us-gaap_DebtAndCapitalLeaseObligations
Less current portion	(42,554)	(52,712)
Total debt outstanding, less current installments	1,004,623	932,075
Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	8.75%
Capital lease obligations
Debt Instrument [Line Items]
Total debt outstanding	101,893	109,351
Other
Debt Instrument [Line Items]
Total debt outstanding	9,627	4,062
Debt discount
Debt Instrument [Line Items]
Total debt outstanding	(14,608)	(13,202)
Senior secured notes due 2022 \| Senior Notes
Debt Instrument [Line Items]
Total debt outstanding	350,000	350,000
Stated interest rate (percent)	8.75%
Term loan facility due 2020 \| Term Notes
Debt Instrument [Line Items]
Total debt outstanding	423,938	350,000
WMLP term loan facility due 2018 \| Term Notes
Debt Instrument [Line Items]
Total debt outstanding	176,327	175,000
Revolving line of credit \| Revolving line of credit
Debt Instrument [Line Items]
Total debt outstanding	$ 0	$ 9,576

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 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

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-Topic 210

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ 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

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Number Topic 6

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