UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 22,262	$ 19,181	$ 20,168	$ 13,261	$ 68,359	$ 54,617
Adjustments to reconcile net income to cash provided by operating activities:
Deferred income tax provision, net					4,386	302
Provision for credit losses					(231)	(139)
Depreciation and amortization					3,214	3,420
Stock-based compensation expense					13,293	10,448
Defined benefit pension plan expense					0	2,157
Loss (gain) on disposal or impairment of assets					155	(1,979)
Noncash lease expense					4,313	3,992
Loss on equity method investment					2,737	1,709
Other					(322)	681
Increase in operating assets
Trade receivables, net					(15,571)	(41,397)
Other assets					(1,989)	(6,384)
Increase (decrease) in operating liabilities
Accrued payroll costs					11,025	7,715
Payment of benefit under terminated pension plan					(19,965)	0
Other liabilities					8,659	24,801
Cash provided by operating activities					78,063	59,943
Cash flows from investing activities:
Capital expenditures					(4,656)	(5,026)
Contributions to WorkLLama joint venture					(500)	(7,000)
Note receivable issued to WorkLLama joint venture					(4,500)	0
Net proceeds from the sale of assets					0	23,742
Cash (used in) provided by investing activities					(9,656)	11,716
Cash flows from financing activities:
Payments on credit facility					(100,000)	0
Repurchases of common stock					(42,103)	(44,407)
Cash dividends					(18,164)	(14,836)
Payments on other financing arrangements					(40)	(271)
Cash used in financing activities					(160,307)	(59,514)
Change in cash and cash equivalents					(91,900)	12,145
Cash and cash equivalents, beginning of period		96,989		103,486	96,989	103,486	$ 103,486
Cash and cash equivalents, end of period	5,089		115,631		5,089	115,631	$ 96,989
Cash Paid During the Period For:
Income taxes					14,348	17,845
Operating lease liabilities					5,413	5,591
Interest, net					918	1,934
Non-Cash Investing and Financing Transactions:
ROU assets obtained from operating leases					274	4,053
Employee stock purchase plan	$ 294	$ 242	$ 193	$ 170	831	558
Unsettled repurchases of common stock					$ 1,030	$ 0