CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities
Net loss	$ (81,618)	$ (20,863)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation and amortization	9,670	9,010
Amortization of debt discount and issuance costs	5,536	960
Accretion of premium on short-term investments and other	72	569
Deferred income taxes	(177)	504
Stock-based compensation	16,006	17,301
Income tax (benefit) charge from stock-based compensation	(267)	249
Restructuring and other	910	0
Goodwill impairment	21,000	0
Changes in operating assets and liabilities, net of impact of acquisition:
Accounts receivable, net	14,567	1,527
Prepaid expenses and other	(108)	(174)
Accounts payable	(831)	2,581
Accrued taxes	(593)	1,110
Accrued compensation and benefits	(822)	1,227
Accrued liabilities and other	461	763
Net cash (used in) provided by operating activities	(16,194)	14,764
Cash flows from investing activities
Acquisition of property and equipment	(7,625)	(3,108)
Cash paid for acquisition, net of cash acquired	(32,550)	0
Purchases of short-term investments	(70,430)	(78,502)
Sales of short-term investments	46,181	5,336
Maturities of short-term investments	4,043	2,000
Net cash used in investing activities	(60,381)	(74,274)
Proceeds from issuance of convertible notes	0	150,000
Issuance costs related to the issuance convertible senior notes	0	(4,350)
Payments of convertible note hedges	0	(31,408)
Proceeds from the issuance of warrants	0	21,763
Cash flows from financing activities
Repayment on capital leases obligations	(321)	(245)
Proceeds from common stock issuances	4,380	21,969
Income tax benefit (charge) from stock-based compensation	267	(249)
Net cash provided by financing activities	4,326	157,480
Net (decrease) increase in cash and cash equivalents	(72,249)	97,970
Effect of exchange rate changes on cash and cash equivalents	1,039	136
Cash and cash equivalents at beginning of period	170,132	76,568
Cash and cash equivalents at end of period	$ 98,922	$ 174,674