The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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Cash received on stock transaction after deduction of issuance costs.

+ References

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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Overview and Basis of Presentation (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 23, 2021	Mar. 29, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Sale of Stock [Line Items]
Issuance costs					$ 0	$ 658	$ 1,600	$ 0
Common Class A
Sale of Stock [Line Items]
Issuance costs			$ 825	$ 13,378
Number of shares issued in conversion (in shares)					1
Common Class B
Sale of Stock [Line Items]
Number of shares issued in conversion (in shares)					1
IPO \| Common Class A
Sale of Stock [Line Items]
Stock sold (in shares)		10,000,000
Price per share (in USD per share)		$ 14.00
Net proceeds		$ 126,600
Issuance costs		$ 13,400
Underwriters' option \| Common Class A
Sale of Stock [Line Items]
Stock sold (in shares)	719,266
Net proceeds	$ 9,200
Issuance costs	$ 800