UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities
Net (loss)	$ (65,379)	$ (91,351)
Adjustments to reconcile net (loss) to cash (used in) operating activities
Stock-based compensation	76,755	60,242
(Gain) on capped call transactions	(19,816)	0
Deferred income taxes	(43,476)	(40,531)
Amortization of deferred commissions	24,922	22,372
Lease expense	11,997	10,454
Amortization of debt discount and issuance costs	10,405	0
Amortization of intangible assets and depreciation	15,677	16,998
Amortization of investments	252	798
Foreign currency transaction (gain) loss	(2,545)	3,577
Other non-cash	(1,374)	(363)
Change in operating assets and liabilities, net	(33,675)	4,342
Cash (used in) operating activities	(26,257)	(13,462)
Investing activities
Purchases of investments	(190,319)	(11,182)
Proceeds from maturities and called investments	0	13,066
Sales of investments	1,424	68,937
Payments for acquisitions, net of cash acquired	0	(10,934)
Investment in property and equipment	(21,806)	(6,439)
Cash (used in) provided by investing activities	(210,701)	53,448
Financing activities
Proceeds from issuance of convertible senior notes	600,000	0
Purchase of capped calls related to convertible senior notes	(51,900)	0
Payment of debt issuance costs	(14,527)	0
Dividend payments to shareholders	(7,206)	(7,105)
Common stock repurchases	(76,737)	(54,836)
Cash provided by (used in) financing activities	449,630	(61,941)
Effect of exchange rate changes on cash and cash equivalents	183	(363)
Net increase (decrease) in cash and cash equivalents	212,855	(22,318)
Cash and cash equivalents, beginning of period	68,363	114,422
Cash and cash equivalents, end of period	$ 281,218	$ 92,104