Intangible Assets, Net - Summary (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Intangible assets
Gross Value	$ 21,511		$ 21,511		$ 20,863
Accumulated Amortization	(7,717)		(7,717)		(5,598)
Net Carrying Value	13,794		13,794		$ 15,265
Amortization expense for intangible assets	1,000	$ 700	$ 2,100	$ 1,400
Weighted Average
Intangible assets
Weighted Average Remaining Useful Life			5 years 4 months 24 days		5 years 10 months 24 days
Client relationships
Intangible assets
Gross Value	11,651		$ 11,651		$ 11,651
Accumulated Amortization	(4,060)		(4,060)		(3,219)
Net Carrying Value	7,591		$ 7,591		$ 8,432
Client relationships | Minimum
Intangible assets
Useful life			2 years		2 years
Client relationships | Maximum
Intangible assets
Useful life			10 years		10 years
Client relationships | Weighted Average
Intangible assets
Weighted Average Remaining Useful Life			7 years 4 months 24 days		7 years 10 months 24 days
Non-compete agreements
Intangible assets
Gross Value	3,410		$ 3,410		$ 3,410
Accumulated Amortization	(1,894)		(1,894)		(1,360)
Net Carrying Value	1,516		$ 1,516		$ 2,050
Non-compete agreements | Minimum
Intangible assets
Useful life			3 years		3 years
Non-compete agreements | Maximum
Intangible assets
Useful life			5 years		5 years
Non-compete agreements | Weighted Average
Intangible assets
Weighted Average Remaining Useful Life			2 years		2 years 3 months 18 days
Trademarks
Intangible assets
Gross Value	140		$ 140		$ 140
Accumulated Amortization	(67)		(67)		(44)
Net Carrying Value	73		$ 73		$ 96
Useful life			3 years		3 years
Trademarks | Weighted Average
Intangible assets
Weighted Average Remaining Useful Life			1 year 7 months 6 days		2 years 1 month 6 days
Internal-Use Software
Intangible assets
Gross Value	6,310		$ 6,310		$ 5,662
Accumulated Amortization	(1,696)		(1,696)		(975)
Net Carrying Value	$ 4,614		$ 4,614		$ 4,687
Internal-Use Software | Minimum
Intangible assets
Useful life			3 years		3 years
Internal-Use Software | Maximum
Intangible assets
Useful life			5 years		5 years
Internal-Use Software | Weighted Average
Intangible assets
Weighted Average Remaining Useful Life			3 years 2 months 12 days		3 years 9 months 18 days