Goodwill and Intangible Assets - Summary of Company's Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 99,865	$ 99,487
Accumulated amortization	(53,792)	(46,617)
Total	46,073	52,870
Intangible assets, gross	100,765	100,387
Intangible assets, net	46,973	53,770
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	75,324	75,181
Accumulated amortization	(38,316)	(32,968)
Total	37,008	42,213
Leasehold benefits
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	2,857	2,715
Accumulated amortization	(2,466)	(2,247)
Total	391	468
Developed technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	14,267	14,186
Accumulated amortization	(7,605)	(6,468)
Total	6,662	7,718
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	2,045	2,045
Accumulated amortization	(1,693)	(1,612)
Total	352	433
Trade names and trademarks
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	5,372	5,360
Accumulated amortization	(3,712)	(3,322)
Total	1,660	2,038
Trade names and trademarks
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets, trade names and trademarks	$ 900	$ 900