CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income (loss)	$ 3,975	$ (7,771)
Adjustments to reconcile net (loss) income to net cash provided by (used in) operating activities:
Depreciation and amortization	6,317	11,469
Recovery from doubtful accounts	1,349	(156)
Stock-based compensation expense	8,132	5,788
Non-cash interest expense	3,408	7,054
Loss (gain) on extinguishment of debt	0	2,878
Unrealized foreign currency transaction losses (gains)	219	237
Provision for (benefit from) deferred taxes	997	(886)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	12,741	14,192
Inventories	788	788
Prepaid expenses and other assets	1,390	(3,526)
Accounts payable	(26,440)	(3,661)
Accrued expenses, compensation and benefits and other liabilities	7,752	(13,035)
Income taxes payable	81	372
Deferred revenue and contract assets	(12,519)	(12,631)
Net cash provided by (used in) operating activities	8,843	1,112
Cash flows from investing activities:
Purchases of property and equipment	(5,619)	(5,629)
Net cash used in investing activities	(5,619)	(5,629)
Cash flows from financing activities:
Proceeds from revolving line of credit	22,000	0
Repayments of Lines of Credit	(22,000)
Proceeds from long-term debt	7,800	79,286
Repayment of debt	(1,474)	(1,113)
Payments for repurchase of outstanding notes	(28,867)	(76,269)
Proceeds from the issuance of common stock under employee stock plans	252	309
Common stock repurchases for tax withholdings for net settlement of equity awards	(2,610)	(3,444)
Partial unwind capped call cash receipt	875	27
Payments for credit facility issuance costs	(289)	(5,979)
Net cash (used in) provided by financing activities	(24,313)	(7,183)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	1,394	(615)
Net increase (decrease) in cash, cash equivalents and restricted cash	(19,695)	(12,315)
Cash, cash equivalents and restricted cash at beginning of period	72,575	68,094
Cash, cash equivalents and restricted cash at end of period	52,880	55,779
Supplemental Cash Flow Information [Abstract]
Cash and cash equivalents at end of period	49,142	52,289
Restricted cash	1,664	1,664
Restricted cash included in other long-term assets	2,074	1,826
Cash paid (refunded) for income taxes	(659)	941
Cash paid for interest	$ 13,579	$ 7,780