Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 61,570	$ 50,377	$ 40,065
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on sale of operations, net of tax	(1,025)	(45)	(855)
Depreciation and amortization expense	23,675	23,061	22,098
Bad debt expense, net of recoveries	3,665	5,137	4,090
Adjustment to contingent earnout liability, net	2,617	(1,494)	(994)
Deferred income taxes	5,775	3,674	4,829
Employee stock awards	6,866	5,705	5,725
Excess tax benefits from share based payment arrangements	(3,260)	(3,837)	(1,108)
Other, net	400	1,178	1,065
Changes in assets and liabilities, net of acquisitions and divestitures:
Accounts receivable, net	(10,668)	(13,849)	(19,188)
Other assets	(3,344)	3,180	(5,612)
Accounts payable	974	3,738	10,217
Income taxes payable	426	(2,071)	1,881
Accrued personnel costs	17,901	(599)	5,496
Other liabilities	(140)	3,508	5,965
Net cash provided by continuing operations	105,432	77,663	73,674
Operating cash flows (used in) provided by discontinued operations	(184)	(627)	387
Net cash provided by operating activities	105,248	77,036	74,061
Cash flows from investing activities:
Business acquisitions and purchases of client lists, net of cash acquired	(29,080)	(28,093)	(5,653)
Purchases of client fund investments	(18,426)	(15,546)	(11,355)
Proceeds from the sales and maturities of client fund investments	12,238	8,785	9,778
Additions to property and equipment	(14,624)	(11,892)	(4,141)
Other, net	2,316	(1,935)	1,524
Net cash used in investing activities	(47,576)	(48,681)	(9,847)
Cash flows from financing activities:
Proceeds from bank debt	690,173	533,900	416,800
Payment of bank debt	(733,173)	(546,800)	(431,200)
Payment for acquisition of treasury stock	(17,484)	(19,735)	(9,144)
(Decrease) increase in client funds obligations	(41,509)	(10,273)	5,257
Payment of contingent consideration of acquisitions	(11,787)	(10,515)	(7,504)
Proceeds from exercise of stock options	6,291	8,008	8,070
Other, net	(1,891)	(178)	(663)
Net cash used in financing activities	(109,380)	(45,593)	(18,384)
Net (decrease) increase in cash, cash equivalents and restricted cash	(51,708)	(17,238)	45,830
Cash, cash equivalents and restricted cash at beginning of year	182,262	199,500	153,670
Cash, cash equivalents and restricted cash at end of year	130,554	182,262	199,500
Reconciliation of cash, cash equivalents and restricted cash to the Consolidated Balance Sheets:
Cash and cash equivalents	640	424	3,494
Restricted cash	27,481	32,985	27,880
Cash equivalents included in funds held for clients	102,433	148,853	168,126
Cash, cash equivalents and restricted cash at end of year	$ 130,554	$ 182,262	$ 199,500