Amount of expense (income) related to adjustment to fair value of warrant liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Fair Value Measurements - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Change in fair value of warrant liabilities	$ (17,072)	$ 7,988	$ 22,649	$ 12,562
Private Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Change in fair value of warrant liabilities	$ 17,100		$ 25,100
Level 3 \| Expected Term \| Private Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants outstanding, measurement input	4.18		4.18
Level 3 \| Price Volatility \| Private Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants outstanding, measurement input	0.651		0.651
Level 3 \| Risk-Free Interest Rate \| Private Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants outstanding, measurement input	0.0079		0.0079