Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	New Accounting Pronouncement, Early Adoption, Effect [Member]	New Accounting Pronouncement, Early Adoption, Effect [Member] Additional Paid-In Capital	New Accounting Pronouncement, Early Adoption, Effect [Member] Accumulated Deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Temporary Equity, Shares Outstanding		28,820
Temporary Equity, Carrying Amount, Attributable to Parent		$ 52,571
Beginning Balance (in shares) at Dec. 31, 2013			11,855
Beginning Balance at Dec. 31, 2013	$ (36,411)		$ 0	$ 25,532	$ 96	$ (62,039)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options (in shares)			1,360
Exercise of common stock options	3,498			3,498
Restricted stock awards, net (in shares)			2,168
Shares withheld related to net share settlement (in shares)			(174)
Shares withheld related to net share settlement	(2,324)			(2,324)
Issuance of common stock related to RSU vesting (in shares)			4
Stock Issued During Period, Value, Stock Warrants Net Exercised	5,983			5,983
Issuance of common stock related to acquisition (in shares)			841
Issuance of common stock related to acquisition	13,342			13,342
Stock-based compensation	24,470			24,470
Other comprehensive loss	(104)				(104)
Unrealized gain on investments, net of tax	(104)
Unrealized gain (loss) on investments, net of tax of $0, $0, and $0 for the years ended December 31 2016, 2015 and 2014, respectively.	0
Net income (loss)	$ (18,673)					(18,673)
Ending Balance (in shares) at Dec. 31, 2014	37,192		37,192
Ending Balance at Dec. 31, 2014	$ 128,752		$ 0	209,472	(8)	(80,712)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period Shares, Stock Warrants Net Exercised		572
Stock Issued During Period, Shares, Conversion of Convertible Securities		(29,392)	(14,696)
Stock Issued During Period, Value, Conversion of Convertible Securities	52,571	$ (52,571)		52,571
Adjustments to Additional Paid in Capital, Warrant Issued	200			200
Stock Issued During Period, Shares, New Issues			6,432
Stock Issued During Period, Value, New Issues	86,200			86,200
Net Exercise Of Warrant, Shares, Common Stock			10
Temporary Equity, Shares Outstanding		0
Temporary Equity, Carrying Amount, Attributable to Parent		$ 0
Exercise of common stock options (in shares)			2,552
Exercise of common stock options	13,533			13,533
Restricted stock awards, net (in shares)			479
Shares withheld related to net share settlement	0			0
Issuance of common stock related to RSU vesting (in shares)			229
Issuance of common stock related to employee stock purchase plan (in shares)			170
Issuance of common stock related to RSU vesting	2,040			2,040
Issuance of common stock related to acquisition (in shares)			0
Issuance of common stock related to acquisition				0
Issuance of common stock and exchange of stock options related to acquisition (in shares)			4,425
Issuance of common stock and exchange of stock options related to acquisition	76,350			76,350
Issuance of common stock for contingent consideration associated with acquisitions (in shares)			1,553
Issuance of common stock for contingent consideration associated with acquisitions	25,608			25,608
Stock-based compensation	31,403			31,403
Other comprehensive loss	(7)				(7)
Unrealized gain on investments, net of tax	61
Unrealized gain (loss) on investments, net of tax of $0, $0, and $0 for the years ended December 31 2016, 2015 and 2014, respectively.	(68)
Net income (loss)	$ 422					422
Ending Balance (in shares) at Dec. 31, 2015	46,600		46,600
Ending Balance at Dec. 31, 2015	$ 278,101		$ 0	359,064	(15)	(80,948)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period Shares, Stock Warrants Net Exercised		0
Stock Issued During Period, Shares, Conversion of Convertible Securities		0
Stock Issued During Period, Value, Conversion of Convertible Securities		$ 0
Retained Earnings (Accumulated Deficit)	(80,290)
Additional Paid in Capital	358,406
Cumulative Effect of New Accounting Principle in Period of Adoption | Accounting Standards Update 2016-09 [Member]							$ 0	$ 658	$ (658)
Temporary Equity, Shares Outstanding		0
Temporary Equity, Carrying Amount, Attributable to Parent		$ 0
Exercise of common stock options (in shares)			2,026
Exercise of common stock options	14,249			14,249
Restricted stock awards, net (in shares)			92
Shares withheld related to net share settlement (in shares)			(493)
Shares withheld related to net share settlement	(6,058)			(6,058)
Issuance of common stock related to RSU vesting (in shares)			945
Issuance of common stock related to employee stock purchase plan (in shares)			208
Issuance of common stock related to RSU vesting	1,886			1,886
Stock-based compensation	29,646			29,646
Other comprehensive loss	(258)				(258)
Unrealized gain on investments, net of tax	(325)
Unrealized gain (loss) on investments, net of tax of $0, $0, and $0 for the years ended December 31 2016, 2015 and 2014, respectively.	67
Net income (loss)	$ (18,053)					(18,053)
Ending Balance (in shares) at Dec. 31, 2016	49,378		49,378
Ending Balance at Dec. 31, 2016	$ 299,513		$ 0	$ 398,787	$ (273)	$ (99,001)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retained Earnings (Accumulated Deficit)	(99,001)
Additional Paid in Capital	$ 398,787
Temporary Equity, Shares Outstanding		0
Temporary Equity, Carrying Amount, Attributable to Parent		$ 0