Concentration Risk, Number of Financial Institutions Holding Cash and Cash Equivalents and Marketable Securities

No definition available.

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- References

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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.

+ References

No definition available.

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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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- Definition

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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Description of Business and Significant Accounting Policies - Concentrations of Credit Risk and Significant Clients (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($) financial_institution	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) financial_institution	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) financial_institution	Dec. 31, 2018 USD ($) financial_institution	Dec. 31, 2017 USD ($)
Accounting Policies [Abstract]
Number of financial institutions holding cash and cash equivalents and marketable securities \| financial_institution	1				1				1	1
Concentration Risk [Line Items]
Revenues	$ 446,960	$ 455,606	$ 462,101	$ 476,111	$ 494,952	$ 505,500	$ 501,587	$ 500,562	$ 1,840,778	$ 2,002,601	$ 1,861,206
Customer Concentration Risk \| Revenue from Contract with Customer \| Genesis
Concentration Risk [Line Items]
Revenues									$ 287,800	$ 386,700
Capital expenditures									15.60%	19.30%