CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net income	$ 41,038	$ 120,968	$ 105,354
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on sale of operations, net of tax	(4,932)	(176)	(413)
Depreciation and amortization expense	48,060	36,269	32,895
Bad debt expense, net of recoveries	3,792	1,551	1,173
Adjustment to contingent earnout liability, net	6,993	2,743	2,435
Deferred income taxes	(8,621)	11,273	13,877
Stock-based compensation expense	13,836	12,286	14,689
Other, net	130	(2,365)	(1,835)
Changes in assets and liabilities, net of acquisitions and divestitures:
Accounts receivable, net	48,218	(36,093)	(61,106)
Other assets	2,809	(6,626)	(11,855)
Accounts payable	(18,846)	2,210	14,363
Income taxes payable	(7,544)	(5,918)	(5,578)
Accrued personnel costs	(5,830)	2,711	24,009
Other liabilities	4,589	14,674	(1,876)
Net cash provided by operating activities	123,692	153,507	126,132
Cash flows from investing activities:
Business acquisitions and purchases of client lists, net of cash acquired	(1,087,521)	(53,110)	(79,141)
Purchases of client fund investments	(23,210)	(14,122)	(19,771)
Proceeds from the sales and maturities of client fund investments	21,923	18,465	12,400
Proceeds from sales of assets and divested operations	7,131	3,059	3,022
Additions to property and equipment	(12,914)	(23,052)	(8,641)
Other, net	(34,692)	(10,633)	(6,987)
Net cash used in investing activities	(1,129,283)	(79,393)	(99,118)
Cash flows from financing activities:
Proceeds from Term Loan	1,400,000	0	0
Proceeds from Revolver	1,087,900	1,224,000	824,900
Payments on Revolver	(1,379,400)	(1,177,300)	(714,500)
Deferred financing costs	(20,654)	0	(2,072)
Payment for acquisition of treasury stock	0	(65,378)	(122,538)
Indirect repurchase of shares for minimum tax withholding	(11,508)	(8,448)	(7,289)
Changes in client funds obligations	16,035	(13,574)	15,352
Payment of contingent consideration of acquisitions and client lists	(56,760)	(45,175)	(21,231)
Proceeds from exercise of stock options	0	8,764	10,035
Net cash provided by (used in) financing activities	1,035,613	(77,111)	(17,343)
Net increase (decrease) in cash, cash equivalents and restricted cash	30,022	(2,997)	9,671
Cash, cash equivalents and restricted cash at beginning of year	157,148	160,145	150,474
Cash, cash equivalents and restricted cash at end of year	187,170	157,148	160,145
Reconciliation of cash, cash equivalents and restricted cash to the Consolidated Balance Sheets:
Cash and cash equivalents	13,826	8,090	4,697
Restricted cash	38,661	30,362	28,487
Cash equivalents included in funds held for clients	134,683	118,696	126,961
Cash, cash equivalents and restricted cash at end of year	187,170	157,148	160,145
Supplemental disclosures of cash flow information:
Cash paid for interest	25,686	19,127	7,421
Cash paid for income taxes, net of income tax refunds	$ 37,537	$ 39,976	$ 27,815