Long-Term Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Long-Term Debt
Coupon interest at 3.75%	$ 3,047	$ 3,047	$ 9,141	$ 9,141
Amortization of debt issuance costs	356	356	1,068	1,068
Total interest expense on Notes	$ 3,403	$ 3,403	$ 10,209	$ 10,209
Coupon interest rate	3.75%	3.75%	3.75%	3.75%

Amount of amortization expense attributable to debt issuance costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

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No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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- Definition

Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

+ References

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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