Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities
Net loss	$ (24,955)	$ (12,825)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,875	5,609
Deferred income taxes	317	271
Bad debt expense and other reserves	109	153
Stock-based compensation	11,540	3,616
Increase in fair value of contingent consideration liability		48
Common stock warrant expense	4,668	1,262
Imputed interest on notes receivable	10	62
Interest income on notes receivable	(18)	(100)
Interest expense on note payable		805
Accretion of beneficial conversion feature on convertible notes payable and discount on revolving line of credit	236	945
Loss on disposal of fixed assets	211	325
Changes in operating assets and liabilities
Accounts receivable	(6,183)	(4,317)
Prepaid expenses	(3,319)	(2,953)
Other current assets	457	(203)
Other assets	(62)	(30)
Accounts payable	491	(1,315)
Accrued employee expenses	(410)	2,521
Other accrued expenses	4,700	178
Other liabilities	(97)	(175)
Net cash used in operating activities	(6,430)	(6,123)
Cash flows from investing activities
Change in restricted cash		2,500
Purchase of property and equipment	(4,790)	(3,320)
Purchase of intangible assets	(350)
Notes receivable from related parties	(60)
Repayment of notes receivable from related parties	3,761
Net cash used in investing activities	(1,439)	(820)
Cash flows from financing activities
Proceeds from initial public offering, net of underwriting discounts	69,674
Repayments under credit agreement	(5,000)
Repurchase of vested common stock option awards		(2,000)
Proceeds from exercise of common stock options	1,760	185
Exercise of warrants	9,461
Net cash provided by (used in) financing activities	75,895	(1,815)
Net increase (decrease) in cash and cash equivalents	68,026	(8,758)
Cash and cash equivalents at beginning of period	43,819	22,062
Cash and cash equivalents at end of period	111,845	13,304
Supplemental disclosures of non-cash activities
Stock-based compensation capitalized for software development	614	251
Capitalized assets included in accounts payable, accrued employee expenses and other accrued expenses	370	53
Conversion of convertible note payable and accrued interest to common stock		$ 25,447