Summary of Significant Accounting Policies - Contract Fulfillment Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Intake Costs asset
Contract With Customer, Asset And Liabilities [Line Items]
Gross Carrying Amount	$ 40,585	$ 41,224
Accumulated Amortization	(23,615)	(23,579)
Net Carrying Amount	16,970	17,645
Capitalized commissions asset
Contract With Customer, Asset And Liabilities [Line Items]
Gross Carrying Amount	73,638	68,008
Accumulated Amortization	(31,259)	(27,178)
Net Carrying Amount	$ 42,379	$ 40,830

Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130533-203044

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