CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
ASSETS
Cash and cash equivalents	$ 261,516	$ 223,310
Accounts receivable, net of allowance for credit losses of $6,753 in 2024 and $7,109 in 2023	303,074	324,915
Inventories	113,426	110,904
Income taxes receivable	8,253	52,269
Prepaid expenses	8,155	12,907
Other current assets	2,551	2,768
Total current assets	696,975	727,073
Property, plant and equipment, less accumulated depreciation of $846,596 in 2024 and $810,933 in 2023	500,492	435,139
Operating lease right-of-use assets	22,902	24,537
Finance lease right-of-use assets	4,534	1,036
Goodwill	50,824	50,824
Other intangibles, net	11,880	12,825
Retirement plan assets	29,613	26,772
Other assets	8,026	8,639
Total assets	1,325,246	1,286,845
Liabilities
Accounts payable	100,276	85,036
Accrued payroll and related expenses	26,503	30,956
Accrued insurance expenses	5,754	5,340
Accrued state, local and other taxes	5,608	4,461
Income taxes payable	303	275
Unearned revenue		15,743
Current portion of operating lease liabilities	6,513	7,367
Current portion of finance lease liabilities and finance obligations	3,828	375
Accrued expenses and other liabilities	2,319	2,304
Total current liabilities	151,104	151,857
Accrued Insurance, Noncurrent	11,316	10,202
Retirement plan liabilities	24,577	23,724
Deferred income taxes	57,958	51,290
Long-term operating lease liabilities	17,308	18,600
Long-term finance lease liabilities	690	819
Other Liabilities, Noncurrent	2,537	7,840
Total liabilities	265,490	264,332
Commitments and contingencies (Note 12)
STOCKHOLDERS' EQUITY
Preferred stock, $0.10 par value, 1,000,000 shares authorized, none issued
Common stock, $0.10 par value, 349,000,000 shares authorized, 215,008,964 and 215,026,458 shares issued and outstanding in 2024 and 2023, respectively	21,501	21,502
Capital in excess of par value	0	0
Retained earnings	1,040,790	1,003,380
Accumulated other comprehensive loss	(2,535)	(2,369)
Total stockholders' equity	1,059,756	1,022,513
Total liabilities and stockholders' equity	$ 1,325,246	$ 1,286,845