Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Finite Lived Intangible Assets [Line Items]
Gross	$ 18,640	$ 18,356
Accumulated Amortization	(8,816)	(6,562)
Foreign Currency Translation	15	24
Net	$ 9,839	$ 11,818
Weighted Average Amortization Period (Years)	4 years	4 years
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Gross	$ 7,164	$ 7,164
Accumulated Amortization	(2,959)	(1,978)
Foreign Currency Translation	13	21
Net	$ 4,218	$ 5,207
Weighted Average Amortization Period (Years)	4 years	4 years
Domain Names
Finite Lived Intangible Assets [Line Items]
Gross	$ 5,252	$ 4,968
Accumulated Amortization	(3,264)	(2,836)
Net	$ 1,988	$ 2,132
Weighted Average Amortization Period (Years)	4 years	4 years
Developed Technologies
Finite Lived Intangible Assets [Line Items]
Gross	$ 4,117	$ 4,117
Accumulated Amortization	(1,405)	(834)
Net	$ 2,712	$ 3,283
Weighted Average Amortization Period (Years)	4 years	5 years
Patents
Finite Lived Intangible Assets [Line Items]
Gross	$ 1,050	$ 1,050
Accumulated Amortization	(657)	(570)
Net	$ 393	$ 480
Weighted Average Amortization Period (Years)	6 years	6 years
Vendor Relationships
Finite Lived Intangible Assets [Line Items]
Gross	$ 890	$ 890
Accumulated Amortization	(389)	(223)
Net	$ 501	$ 667
Weighted Average Amortization Period (Years)	2 years	3 years
Trade Names
Finite Lived Intangible Assets [Line Items]
Gross	$ 167	$ 167
Accumulated Amortization	(142)	(121)
Foreign Currency Translation	2	3
Net	$ 27	$ 49
Weighted Average Amortization Period (Years)	1 year	2 years