Debt - Exchangeable Senior Notes - Interest expense (Details) - Exchangeable Senior Notes - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Cash coupon	$ 55	$ 1,348	$ 331	$ 2,696
Amortization of debt discount		284		566
Amortization of issuance cost	13	247	71	490
Total interest expense	$ 68	$ 1,879	$ 402	$ 3,752

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

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Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration