Long-Lived Assets - Summary of Carrying Values of Contract Cost Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	$ 80,340
Accumulated Amortization	(43,051)	$ 0
Net Amount	37,289
Client contract incentives
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	28,366
Accumulated Amortization	(20,833)
Net Amount	7,533
Capitalized costs
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	44,469
Accumulated Amortization	(20,230)
Net Amount	24,239
Capitalized commission fees
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	7,505
Accumulated Amortization	(1,988)
Net Amount	$ 5,517

Amount of accumulated amortization of asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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