Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 222,903	$ 263,958
Accounts receivable less allowances	184,961	181,511
Inventories	10,735	12,004
Prepaid income taxes	17,084	13,166
Prepaid expenses	28,929	30,204
Total current assets	464,612	500,843
Investments of deferred compensation plans held in trust	120,784	106,126
Properties and equipment, at cost, less accumulated depreciation of $373,912 (2023- $354,872)	202,249	203,840
Lease right of use asset	132,262	126,387
Identifiable intangible assets less accumulated amortization of $54,031 (2023 - $48,965)	97,035	90,264
Goodwill	662,124	585,017
Other assets	55,918	55,618
Total Assets	1,734,984	1,668,095
Current liabilities
Accounts payable	43,001	64,034
Income taxes		6,858
Accrued insurance	59,899	58,568
Accrued compensation	78,374	88,381
Short-term lease liability	41,169	38,635
Other current liabilities	39,310	55,574
Total current liabilities	261,753	312,050
Deferred income taxes	27,901	30,321
Deferred compensation liabilities	119,780	104,069
Long-term lease liability	105,233	100,776
Other liabilities	13,020	13,003
Total Liabilities	527,687	560,219
Commitments and contingencies (Note 10)
STOCKHOLDERS' EQUITY
Capital stock - authorized 80,000,000 shares $1 par; issued 37,312,834 shares (2023 - 37,183,681 shares)	37,313	37,184
Paid-in capital	1,416,166	1,341,273
Retained earnings	2,570,722	2,446,925
Treasury stock - 22,317,642 shares (2023 - 22,148,927 shares)	(2,819,053)	(2,719,588)
Deferred compensation payable in Company stock	2,149	2,082
Total Stockholders' Equity	1,207,297	1,107,876
Total Liabilities and Stockholders' Equity	$ 1,734,984	$ 1,668,095