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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Number of shares issued for each share of convertible preferred stock that is converted.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Specific incremental costs directly attributable to a proposed or actual offering of securities which are deferred at the end of the reporting period.

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Amount of investment in equity security without readily determinable fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Cash paid for expenses incurred during underwriting activities (the process to review insurance applications, evaluate risks, accept or reject applications, and determine the premiums to be charged) for insurance companies.

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

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Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Cash received on stock transaction after deduction of issuance costs.

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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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Description of Business and Significant Accounting Policies (Details) - USD ($)				1 Months Ended		12 Months Ended
	Apr. 13, 2021	Dec. 16, 2020	Nov. 30, 2020	Mar. 31, 2021	Apr. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Offering price per share (in dollars per share)	$ 120.00
Net proceeds from sale of stock	$ 263,900,000
Underwriting discount	11,000,000
Offering expense	$ 1,000,000
Non-marketable equity security						$ 40,000,000	$ 0
Period of payment deferral					6 months
Repayments of debt						71,316,000	148,113,000	$ 109,939,000
Impairment, Long-Lived Asset, Held-for-Use						0	$ 0
Senior Notes
Short-term Debt [Line Items]
Carrying amount of convertible senior notes						646,900,000
Carrying amount of convertible senior notes						646,900,000
Fair Value, Inputs, Level 2 \| Senior Notes
Short-term Debt [Line Items]
Fair value of convertible senior notes						627,500,000
Fair value of convertible senior notes						$ 627,500,000
Internally developed software
Short-term Debt [Line Items]
Estimated useful lives						three years
Computer and networking equipment
Short-term Debt [Line Items]
Estimated useful lives						three years
Furniture and fixtures
Short-term Debt [Line Items]
Estimated useful lives						three years
Series B
Short-term Debt [Line Items]
Shares of preferred stock purchased (in shares)			600,208
Common Stock
Short-term Debt [Line Items]
Preferred stock converted to common stock (in shares)		600,208
Convertible preferred stock converted to common stock (in shares)		47,349,577
Public Stock Offering
Short-term Debt [Line Items]
Shares sold in offering	2,300,000
Over-Allotment Option
Short-term Debt [Line Items]
Shares sold in offering	300,000
IPO
Short-term Debt [Line Items]
Shares sold in offering		9,000,000
Offering price per share (in dollars per share)		$ 20.00
Net proceeds from sale of stock		$ 167,400,000
Underwriting discount		12,600,000
Deferred offering costs		$ 7,900,000
Paycheck Protection Program Loan, CARES Act
Short-term Debt [Line Items]
Aggregate principal amount					$ 5,300,000
Stated interest rate					1.00%
Repayments of debt				$ 5,300,000