UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net (loss)	$ (25,794)	$ (65,379)
Adjustments to reconcile net (loss) to cash (used in) operating activities
Stock-based compensation	89,483	76,755
Loss (gain) on capped call transactions	7,543	(19,816)
Deferred income taxes	(53,638)	(43,476)
Amortization of deferred commissions	31,388	24,922
Amortization of debt discount and issuance costs	2,025	10,405
Amortization of intangible assets and depreciation	24,030	15,677
Amortization of investments	2,916	252
Foreign currency transaction loss (gain)	4,983	(2,545)
Other non-cash	(8,421)	10,623
Change in operating assets and liabilities, net	(79,836)	(33,675)
Cash (used in) operating activities	(5,321)	(26,257)
Investing activities
Purchases of investments	(67,170)	(190,319)
Proceeds from maturities and called investments	96,859	0
Sales of investments	25,123	1,424
Payments for acquisitions, net of cash acquired	(4,993)	0
Investment in property and equipment	(7,089)	(21,806)
Cash provided by (used in) investing activities	42,730	(210,701)
Financing activities
Proceeds from issuance of convertible senior notes	0	600,000
Purchase of capped calls related to convertible senior notes	0	(51,900)
Payment of debt issuance costs	0	(14,527)
Proceeds from employee stock purchase plan	7,786	1,403
Dividend payments to stockholders	(7,310)	(7,206)
Common stock repurchases	(91,907)	(78,140)
Cash (used in) provided by financing activities	(91,431)	449,630
Effect of exchange rate changes on cash and cash equivalents	(1,466)	183
Net (decrease) increase in cash and cash equivalents	(55,488)	212,855
Cash and cash equivalents, beginning of period	171,899	68,363
Cash and cash equivalents, end of period	$ 116,411	$ 281,218