Long-Term Debt - Schedule of Outstanding Senior Notes Issuances (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ 262,500	$ 262,500
Less: unamortized issuance costs	7,429	7,592
Senior notes, net	255,071	254,908
Senior Notes
Debt Instrument [Line Items]
Principal amount	262,500	262,500
Less: unamortized issuance costs	7,429	7,592
Senior notes, net	255,071	254,908
Senior Notes \| 2016 Senior Notes
Debt Instrument [Line Items]
Principal amount	110,000	110,000
Less: unamortized issuance costs	3,528	3,565
Senior notes, net	106,472	106,435
Original debt issuance costs	$ 3,715
Coupon rate	6.625%
Effective interest rate	7.07%
Senior Notes \| 2013 Senior Notes
Debt Instrument [Line Items]
Principal amount	$ 152,500	152,500
Less: unamortized issuance costs	3,901	4,027
Senior notes, net	148,599	$ 148,473
Original debt issuance costs	$ 5,054
Coupon rate	7.75%
Effective interest rate	8.04%

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.

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

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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