CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 42,998	$ 6,865
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization	19,169	13,936
Provision (recovery) for doubtful accounts	890	(175)
Stock-based compensation expense	6,116	7,731
Non-cash provision for restructuring	1,137	0
Non-cash interest expense	7,935	1,544
Unrealized foreign currency transaction losses (gains)	2,021	(5,098)
Benefit for deferred taxes	(5,187)	(6,504)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	17,057	6,844
Inventories	(7,561)	4,028
Prepaid expenses and other current assets	(1,493)	1,772
Accounts payable	(19,627)	4,932
Accrued expenses, compensation and benefits and other liabilities	(4,384)	(17,764)
Income taxes payable	347	1,268
Deferred revenues	(108,343)	(55,466)
Net cash used in operating activities	(48,925)	(36,087)
Cash flows from investing activities:
Purchases of property and equipment	(9,681)	(11,110)
Payments for business and technology acquisitions, net of cash acquired	0	(65,967)
Increase in other long-term assets	(17)	(575)
Increase in restricted cash	(4,544)	(1,047)
Net cash used in investing activities	(14,242)	(78,699)
Cash flows from financing activities:
Proceeds from long-term debt	100,000	120,401
Repayment of debt	(2,500)	0
Payments for Repurchase of Common Stock	0	(7,999)
Cash paid for capped call transactions	0	(10,125)
Proceeds from the issuance of common stock under employee stock plans	5,914	3,113
Common stock repurchases for tax withholdings for net settlement of equity awards	(803)	(1,442)
Proceeds from revolving credit facilities	25,000	49,500
Payments on revolving credit facilities	(30,000)	(39,500)
Payments for credit facility issuance costs	(5,020)	(1,193)
Net cash provided by financing activities	92,591	112,755
Effect of exchange rate changes on cash and cash equivalents	391	(1,045)
Net increase (decrease) in cash and cash equivalents	29,815	(3,076)
Cash and cash equivalents at beginning of period	17,902	25,056
Cash and cash equivalents at end of period	47,717	21,980
Supplemental Cash Flow Information [Abstract]
Cash paid for income taxes, net of refunds	1,678	1,538
Cash paid for interest	$ 5,767	$ 1,492