Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities
Net income	$ 201,438	$ 147,273
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	67,783	48,254
Accretion of discount on available-for-sale securities	(872)	(276)
Non-cash marketing expense	1,320	618
Loss on disposition of property and equipment		146
Amortization of debt issuance costs	532	27
Stock-based compensation expense	70,815	76,364
Cash paid for derivative settlement	205	(558)
Gain on derivative	(1,559)	(305)
Deferred income taxes, net	(4,841)	12,630
Other	(227)
Changes in operating assets and liabilities:
Accounts receivable	(5,406)	(3,874)
Prepaid expenses	(11,203)	(8,789)
Inventory	27	97
Other assets	(10,104)	671
Deferred contract costs	(86,634)	(68,041)
Accounts payable	4,159	1,659
Income taxes, net	1,245	236
Accrued commissions and bonuses	(3,320)	(1,272)
Accrued payroll and vacation	1,810	11,609
Deferred revenue	12,585	11,051
Accrued expenses and other current liabilities	(1,106)	2,117
Net cash provided by operating activities	236,647	229,637
Cash flows from investing activities
Purchases of investments from funds held for clients	(268,718)	(170,760)
Proceeds from investments from funds held for clients	328,731	195,000
Purchases of intangible assets		(1,500)
Purchases of property and equipment	(92,041)	(86,718)
Net cash used in investing activities	(32,028)	(63,978)
Cash flows from financing activities
Proceeds from issuance of debt	29,000
Repurchases of common stock	(94,652)
Withholding taxes paid related to net share settlements	(5,017)	(61,149)
Payments on long-term debt	(29,287)	(1,331)
Net change in client funds obligation	(92,478)	1,346,479
Payment of debt issuance costs	(6,437)
Net cash used in (provided by) financing activities	(198,871)	1,283,999
Increase in cash, cash equivalents, restricted cash and restricted cash equivalents	5,748	1,449,658
Cash, cash equivalents, restricted cash and restricted cash equivalents
Cash, cash equivalents, restricted cash and restricted cash equivalents, beginning of period	1,812,691	1,585,275
Cash, cash equivalents, restricted cash and restricted cash equivalents, end of period	1,818,439	3,034,933
Cash and cash equivalents	317,163	230,926
Restricted cash included in funds held for clients	1,501,276	2,804,007
Non-cash investing and financing activities:
Purchases of property and equipment, accrued but not paid	3,355	5,994
Stock-based compensation for capitalized software	6,545	5,108
Right of use assets obtained in exchange for operating lease liabilities	$ 14,385	$ 4,439