CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
ASSETS
Cash and cash equivalents	$ 80,835	$ 84,496
Accounts receivable, net of allowance for doubtful accounts of $7,342 in 2021 and $5,181 in 2020	238,192	161,771
Inventories	79,881	82,918
Income taxes receivable	51,021	82,943
Prepaid expenses	4,371	9,124
Assets held for sale	692	4,032
Other current assets	2,863	3,075
Total current assets	457,855	428,359
Property, plant and equipment, less accumulated depreciation of $792,763 in 2021 and $790,712 in 2020	253,095	264,411
Operating lease right-of-use assets	21,408	27,270
Finance lease right-of-use assets	21,415
Goodwill	32,150	32,150
Other assets	40,717	38,315
Total assets	826,640	790,505
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable	60,862	41,080
Accrued payroll and related expenses	17,146	18,428
Accrued insurance expenses	6,555	5,489
Accrued state, local and other taxes	4,603	2,788
Income taxes payable	689	1,115
Current portion of operating lease liabilities	7,197	9,192
Current portion of finance lease liabilities	21,382
Other accrued expenses	2,287	1,473
Total current liabilities	120,721	79,565
Long-term accrued insurance expenses	13,652	11,822
Long-term pension liabilities	30,945	33,080
Deferred income taxes	9,099	13,332
Long-term operating lease liabilities	16,066	21,090
Other long-term liabilities	5,374	49
Total liabilities	195,857	158,938
STOCKHOLDER'S EQUITY
Common stock	21,564	21,495
Capital in excess of par value	0	0
Retained earnings	626,501	627,778
Accumulated other comprehensive loss	(17,282)	(17,706)
Total stockholders' equity	630,783	631,567
Total liabilities and stockholders' equity	$ 826,640	$ 790,505