Long Term Obligations (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Senior secured notes due 2019 (2019 Notes)	$ 132,271	$ 125,827
4.75% convertible notes due 2018 (2018 Convertible Notes)	99,053	97,087
Capital leases	202	233
Long-term obligations gross	231,526	223,147
Less-current portion of capital leases	59	60
Total	231,467	223,087
Senior Notes Due 2019
Debt Instrument [Line Items]
Senior secured notes due 2019 (2019 Notes)	132,271	125,827
Senior Convertible Notes Due 2018
Debt Instrument [Line Items]
4.75% convertible notes due 2018 (2018 Convertible Notes)	$ 99,053	$ 97,087

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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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 and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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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.

+ References

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

-Publisher FASB

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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.

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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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