Condensed 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)	$ (46,409)	$ (3,545)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	8,425	5,800
Non-cash operating lease cost	5,594	3,538
Stock-based compensation	51,284	22,195
Accretion of discounts and premiums on investments, net	(83)	(2,472)
Amortization of debt discount and issuance costs	23,553	10,949
Deferred income taxes	(4,266)	(27,267)
Loss on induced conversion and debt extinguishment	1	20,507
Other non-cash operating activities, net	4,922	1,143
Changes in operating assets and liabilities, net of effect of business acquisitions:
Accounts receivable	67,148	26,698
Deferred commissions	(1,283)	(4,882)
Prepaid expenses, other current assets, and other assets	(45,807)	(28,949)
Accounts payable	(3,056)	5,165
Accrued payroll and payroll related liabilities	(20,507)	1,703
Accrued expenses, other current liabilities, operating lease liabilities, and other liabilities	(11,085)	441
Deferred revenue	(12,138)	(17,538)
Net cash provided by operating activities	16,293	13,486
Cash flows from investing activities:
Purchases of property and equipment	(14,257)	(6,160)
Cash paid in business acquisitions, net of cash acquired	0	(16,604)
Purchases of investments	(884,063)	(235,973)
Sales and maturities of investments	564,274	231,794
Net cash used in investing activities	(334,046)	(26,943)
Cash flows from financing activities:
Proceeds from issuance of convertible senior notes, net of issuance costs	0	783,946
Principal payments on 2023 convertible senior notes	(11)	(145,241)
Purchase of capped calls	0	(87,360)
Proceeds from receipt of Section 16(b) disgorgement	0	4,918
Proceeds from exercise of stock options	20,502	18,065
Minimum tax withholding paid on behalf of employees for restricted stock units	(15,895)	(6,395)
Other financing activity	(527)	(1,305)
Net cash provided by financing activities	4,069	566,628
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(311)	(323)
Net increase (decrease) in cash, cash equivalents and restricted cash	(313,995)	552,848
Cash, cash equivalents and restricted cash—beginning of period	411,424	90,961
Cash, cash equivalents and restricted cash—end of period	97,429	643,809
Supplemental disclosure of cash flow information:
Cash paid for interest	6,029	718
Cash paid for income taxes	1,788	1,280
Cash paid for amounts included in the measurement of operating lease liabilities	7,177	4,468
Supplemental disclosure of noncash investing and financing activities:
Property and equipment recorded in accounts payable and accrued expenses and other current liabilities	5,316	1,097
Right-of-use assets obtained in exchange for new operating lease liabilities	34,915	12,909
Reduction of right-of-use assets due to remeasurement	(5,948)	0
Consideration for business acquisition included in accrued expenses and other current liabilities and other liabilities	0	3,000
Contingent consideration settled through issuance of common stock	0	750
Debt issuance costs recorded in accounts payable and accrued expenses and other current liabilities	$ 0	$ 657