Balance Sheet Components (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Cash and cash equivalents
Cash	$ 19,751	$ 8,598
Cash equivalents:
Money market funds	93,077	104,021
Certificates of deposit	25	25
Total cash equivalents	93,102	104,046
Cash and cash equivalents	112,853	112,644	$ 118,794	$ 128,299
Accounts Receivable
Accounts receivable	42,254	38,260
Allowance for doubtful accounts	(369)	(393)
Accounts receivable, net	41,885	37,867
Property and equipment, net
Total property and equipment	41,385	29,740
Less accumulated depreciation	(20,390)	(12,908)
Property and equipment, net	20,995	16,832
Computer equipment
Property and equipment, net
Total property and equipment	25,623	18,384
Software
Property and equipment, net
Total property and equipment	2,914	2,417
Office furniture
Property and equipment, net
Total property and equipment	2,641	2,071
Leasehold improvements
Property and equipment, net
Total property and equipment	7,096	5,123
Construction in progress
Property and equipment, net
Total property and equipment	$ 3,111	$ 1,745