Fair value measurements.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

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Fair Value Measurements - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		9 Months Ended
	Mar. 31, 2021	Feb. 28, 2021	Sep. 30, 2021	Sep. 30, 2020
Fair Value Measurements [Line Items]
Proceeds from warrant exercises			$ 183,007	$ 0
Warrants outstanding (in shares)			0
Series E-2 Preferred Shares \| Traton
Fair Value Measurements [Line Items]
Warrants to purchase preferred stock (in shares)		4,331,644
Exercise price per share (in dollars per share)		$ 11.31
Proceeds from warrant exercises		$ 49,000
Series E Redeemable Convertible Preferred Stock \| Navistar, Inc.
Fair Value Measurements [Line Items]
Warrants to purchase preferred stock (in shares)	9,477,073
Exercise price per share (in dollars per share)	$ 14.14
Proceeds from warrant exercises	$ 134,000