Fair Value Measurements Narrative (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value of senior secured notes	$ 265,500
Carrying value of senior secured notes	218,657
Estimated fair value of convertible debt	107,858
Carrying value of convertible debt	37,954
Estimated fair value of the line of credit	8,325
Carrying value of the line of credit	8,750
Forward Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Notional Amount	16,073
Gain (Losses) as a result of changes in the fair value of the contracts	(1,299)	376
Derivative Asset, Fair Value, Gross Asset		$ 5
Convertible Notes due December 15, 2017 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stock price at the end of the period	$ 17.50
Expected volatility	28.00%
Credit spreads	7.51%
Risk-free interest rate	0.71%

The fair value of senior notes as of the balance sheet date.

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Fair value of convertible debt at the balance sheet date.

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-Name Accounting Standards Codification

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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

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- Definition

Risk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.

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- Definition

Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

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Fair value of the amount outstanding under the credit facility.

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- Definition

Including the current and noncurrent portions, 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). Senior note holders are paid off in full before any payments are made to junior note holders.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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