Long term debt (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
7.75% senior notes	$ 610,000us-gaap_SeniorLongTermNotes	$ 610,000us-gaap_SeniorLongTermNotes
Less: Current portion of long-term debt	0us-gaap_LongTermDebtCurrent	0us-gaap_LongTermDebtCurrent
Long-term debt, net	2,486,177us-gaap_LongTermNotesAndLoans	2,485,127us-gaap_LongTermNotesAndLoans
Term Loan and Securitization Facility:
Debt Instrument [Line Items]
Less: term loan discount	(27,698)	(28,748)
Total Term Loan and Securitization Facility	1,876,177	1,875,127
7.75% senior notes
Debt Instrument [Line Items]
7.75% senior notes	610,000	610,000
Term loan \| Term Loan and Securitization Facility:
Debt Instrument [Line Items]
Term Loan and Securitization Facility:	1,903,875	1,903,875
Securitization facility \| Term Loan and Securitization Facility:
Debt Instrument [Line Items]
Term Loan and Securitization Facility:	$ 0	$ 0

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

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- Definition

Carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the operating cycle if longer, excluding current portion.

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Carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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