Fair Value Measurements - Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Liabilities
Conversion option liability	$ 10,207	$ 8,783
Corporate bonds
Assets
Debt securities	126,352	82,086
Preferred stock
Assets
Preferred stock	14,229	21,603
Recurring
Assets
Marketable securities	161,042	103,689
Liabilities
Total liabilities	39,763	54,834
Recurring \| U.S. treasury securities
Assets
Debt securities	20,461	0
Recurring \| Corporate bonds
Assets
Debt securities	126,352	82,086
Recurring \| Preferred stock
Assets
Preferred stock	14,229	21,603
Recurring \| Warrant liabilities
Liabilities
Warrant liabilities	29,556	46,051
Recurring \| Conversion option liability
Liabilities
Conversion option liability	10,207	8,783
Recurring \| Level 1
Assets
Marketable securities	20,461	0
Liabilities
Total liabilities	3,824	12,377
Recurring \| Level 1 \| U.S. treasury securities
Assets
Debt securities	20,461	0
Recurring \| Level 1 \| Corporate bonds
Assets
Debt securities	0	0
Recurring \| Level 1 \| Preferred stock
Assets
Preferred stock	0	0
Recurring \| Level 1 \| Warrant liabilities
Liabilities
Warrant liabilities	3,824	12,377
Recurring \| Level 1 \| Conversion option liability
Liabilities
Conversion option liability	0	0
Recurring \| Level 2
Assets
Marketable securities	140,581	103,689
Liabilities
Total liabilities	0	0
Recurring \| Level 2 \| U.S. treasury securities
Assets
Debt securities	0	0
Recurring \| Level 2 \| Corporate bonds
Assets
Debt securities	126,352	82,086
Recurring \| Level 2 \| Preferred stock
Assets
Preferred stock	14,229	21,603
Recurring \| Level 2 \| Warrant liabilities
Liabilities
Warrant liabilities	0	0
Recurring \| Level 2 \| Conversion option liability
Liabilities
Conversion option liability	0	0
Recurring \| Level 3
Assets
Marketable securities	0	0
Liabilities
Total liabilities	35,939	42,457
Recurring \| Level 3 \| U.S. treasury securities
Assets
Debt securities	0	0
Recurring \| Level 3 \| Corporate bonds
Assets
Debt securities	0	0
Recurring \| Level 3 \| Preferred stock
Assets
Preferred stock	0	0
Recurring \| Level 3 \| Warrant liabilities
Liabilities
Warrant liabilities	25,732	33,674
Recurring \| Level 3 \| Conversion option liability
Liabilities
Conversion option liability	$ 10,207	$ 8,783

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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