Intangible Assets and Goodwill - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Intangible Assets And Goodwill [Line Items]
Amortization expense	$ 2,500	$ 3,070	$ 7,717	$ 9,796
Amortization expense related to capitalized internal-use software	3,100	$ 3,700	8,900	$ 10,900
Capitalized internal-use software, net	28,569		28,569		$ 29,462
Capitalized Internal-Use Software Net in Development Phase
Intangible Assets And Goodwill [Line Items]
Capitalized internal-use software, net	$ 13,200		$ 13,200

Intangible assets and goodwill.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of expense for amortization of capitalized computer software costs.

+ References

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- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

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