Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities
Net income	$ 247,187	$ 119,296
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	32,468	26,272
Accretion of discount on available-for-sale securities	(73)	(124)
Non-cash marketing expense	398	418
Loss (Gain) on disposition of property and equipment	10	(13)
Amortization of debt issuance costs	276	308
Stock-based compensation expense	(93,790)	27,819
Deferred income taxes, net	(10,489)	(1,650)
Other	(100)	78
Changes in operating assets and liabilities:
Accounts receivable	(3,555)	5,041
Prepaid expenses	(13,888)	(6,984)
Inventory	182	385
Other assets	572	2,923
Deferred contract costs	(37,640)	(38,519)
Accounts payable	2,980	(4,645)
Income taxes, net	35,673	24,933
Accrued commissions and bonuses	(10,401)	(10,845)
Accrued payroll and vacation	(13,636)	(8,835)
Deferred revenue	6,570	3,386
Accrued expenses and other current liabilities	5,892	6,859
Net cash provided by operating activities	148,636	146,103
Cash flows from investing activities
Purchases of investments from funds held for clients	0	(25,000)
Proceeds from investments from funds held for clients	90,000	25,000
Purchases of property and equipment	(47,728)	(40,618)
Proceeds from sale of property and equipment	13
Net cash provided by (used in) investing activities	42,285	(40,618)
Cash flows from financing activities
Withholding taxes paid related to net share settlements	(3,052)	(626)
Dividends paid	(21,209)
Net change in client funds obligation	400,355	183,629
Net cash provided by financing activities	376,094	183,003
Increase in cash, cash equivalents, restricted cash and restricted cash equivalents	567,015	288,488
Cash, cash equivalents, restricted cash and restricted cash equivalents
Cash, cash equivalents, restricted cash and restricted cash equivalents, beginning of period	2,422,760	2,409,095
Cash, cash equivalents, restricted cash and restricted cash equivalents, end of period	2,989,775	2,697,583
Cash and cash equivalents	371,325	505,590
Restricted cash included in funds held for clients	2,618,450	2,191,993
Total cash, cash equivalents, restricted cash and restricted cash equivalents, end of period	2,989,775	2,697,583
Non-cash investing and financing activities:
Purchases of property and equipment, accrued but not paid	9,070	6,991
Stock-based compensation for capitalized software	3,589	3,597
Right of use assets obtained in exchange for operating lease liabilities	$ 5,080	$ 1,933