Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net income	$ 11,329	$ 24,653
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	4,147	3,607
Bad debt provision	2,851	3,415
Share-based compensation expense	2,396	2,271
Amortization of premium on marketable securities	561	536
Unrealized loss (gain) on deferred compensation fund investments	4,074	(1,146)
Changes in other long-term liabilities	(1,760)	0
Net loss on disposals of fixed assets	173	268
Changes in operating assets and liabilities:
Accounts and notes receivable	(27,222)	1,903
Inventories and supplies	1,195	2,416
Prepaid expenses and other assets	(2,462)	(19,814)
Deferred compensation funding	3,605	990
Accounts payable and other accrued expenses	(3,051)	6,064
Accrued payroll, accrued and withheld payroll taxes	(24,933)	(30,747)
Income taxes receivable	3,764	7,908
Accrued insurance claims	3,056	622
Deferred compensation liability	(7,905)	556
Net cash (used in) provided by operating activities	(30,182)	3,502
Cash flows from (used in) investing activities:
Disposals of fixed assets	152	54
Additions to property and equipment	(1,407)	(850)
Purchases of marketable securities	(1,525)	(7,902)
Sales of marketable securities	1,519	4,995
Cash paid for acquisitions	(114)	0
Net cash used in investing activities	(1,375)	(3,703)
Cash flows from financing activities:
Dividends paid	(15,704)	(15,472)
Reissuance of treasury stock pursuant to Dividend Reinvestment Plan	25	23
Proceeds from the exercise of stock options	410	1,475
Proceeds from short-term borrowings	10,000	0
Payments of statutory withholding on net issuance of restricted stock units	(1,069)	(1,501)
Net cash used in financing activities	(6,338)	(15,475)
Net change in cash and cash equivalents	(37,895)	(15,676)
Cash and cash equivalents at beginning of the period	70,794	139,330
Cash and cash equivalents at end of the period	$ 32,899	$ 123,654