For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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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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Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
Geographic Information (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Geographic revenue based on customer location and long-lived tangible assets
Revenue	$ 194,439	$ 165,227	$ 567,632	$ 485,742
Total long-lived tangible assets	48,866		48,866		$ 50,906
North America
Geographic revenue based on customer location and long-lived tangible assets
Revenue	77,264	59,252	210,527	$ 172,481
Total long-lived tangible assets	41,260		$ 41,260		$ 43,451
United States \| Revenue benchmark \| Geographic concentration
Geographic revenue based on customer location and long-lived tangible assets
Concentration risk percentage			33.00%	32.00%
United States \| Total long-lived tangible assets \| Geographic concentration
Geographic revenue based on customer location and long-lived tangible assets
Concentration risk percentage			76.00%		75.00%
Europe
Geographic revenue based on customer location and long-lived tangible assets
Revenue	60,301	53,291	$ 187,356	$ 159,294
Total long-lived tangible assets	7,424		$ 7,424		$ 7,192
IRELAND \| Total long-lived tangible assets \| Geographic concentration
Geographic revenue based on customer location and long-lived tangible assets
Concentration risk percentage			11.00%
Rest of the world
Geographic revenue based on customer location and long-lived tangible assets
Revenue	56,874	$ 52,684	$ 169,749	$ 153,967
Total long-lived tangible assets	$ 182		$ 182		$ 263