Property and Equipment, Net - Narrative (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 1,582	[1]	$ 909	[1]
Leasehold Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years
Office and Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	3 years
Office and Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	3 years

[1] Amounts are included in the cost of services, development, sales and marketing, and general and administrative expense line items of the consolidated statements of operations.