Long-Lived Assets - Summary of Carrying Values of Contract Cost Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	$ 66,459
Accumulated Amortization	(30,932)	$ 0
Net Amount	35,527
Client contract incentives
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	26,766
Accumulated Amortization	(15,272)
Net Amount	11,494
Capitalized costs
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	33,619
Accumulated Amortization	(14,744)
Net Amount	18,875
Capitalized commission fees
Capitalized Contract Cost [Line Items]
Gross Carrying Amount	6,074
Accumulated Amortization	(916)
Net Amount	$ 5,158

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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