Debt Obligations - 2022 Convertible Notes Interest Expense Components (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt Instrument
Amortization of debt discount and debt issuance costs			$ 4,677	$ 2,064
Total interest expense	$ 6,580	$ 5,747	15,549	11,395
8.2% Convertible Notes due 2022 \| Convertible Notes
Debt Instrument
Stated coupon interest		2,050	2,050	4,100
Amortization of debt discount and debt issuance costs		485	521	960
Total Interest expense		2,535	2,571	5,060
1.5% Convertible Senior Subordinated Notes due 2026 \| Convertible Notes
Debt Instrument
Stated coupon interest	862	862	1,725	1,725
Amortization of debt discount and debt issuance costs	321	314	640	626
Total Interest expense	$ 1,183	$ 1,176	$ 2,365	$ 2,351

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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

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