Internally Developed Software - Components of Internally Developed Software (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Internally developed software	$ 209,703	$ 159,619
Less: accumulated amortization	(84,113)	(63,118)
Internally developed software, net	$ 125,590	$ 96,501
Internally developed software
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years

For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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