Long-Term Debt - Convertible Debt (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt	$ 20,344	$ 45,286
Convertible senior subordinated debentures at 4.125%, due in February 2027 \| Convertible Subordinated Debt
Debt Disclosure [Abstract]
Initial conversion price	$ 24.79
Debt Instrument [Line Items]
Interest rate (as a percent)	4.125%
Carrying amount of equity component	25,381	25,381
Principal amount of liability component	13,350	13,350
Unamortized discount	(1,999)	(2,709)
Long-term debt	$ 11,351	$ 10,641

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or 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 20

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

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-Name Accounting Standards Codification

-Topic 210

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

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The price per share of the conversion feature embedded in the debt instrument.

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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

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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.

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- Definition

Amount of long-term debt and capital lease obligations including current maturities.

+ References

No definition available.

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