Long-Term Debt - Convertible Senior Notes Dues 2032 (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended
Mar. 31, 2012	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Carrying amount		$ 756,935
Unamortized debt discount		13,396
Convertible Senior Notes Maturing March 2032 [Member]
Debt Instrument [Line Items]
Carrying amount	$ 200,000	200,000	$ 200,000
Interest rate (as a percent)	3.25%
Frequency of periodic payment	semi-annually
Maturity date	Mar. 15, 2032
Initial conversion ratio	0.0399752
Initial conversion price per share	$ 25.02
Redemption price as a percentage of principal amount	100.00%
Repurchase price as a percentage of principal amount	100.00%
Expected life used to estimate fair value	6 years
Effective interest rate (as a percent)	6.90%
Carrying amount of equity component	$ 22,500
Unamortized debt discount	$ 35,400	$ 13,396	$ 15,000

Debt Instrument, Repurchase Amount, Percentage

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

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

+ References

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- Definition

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

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Percentage of principal amount of debt redeemed.

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No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

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