CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 87,827	$ 51,331
Accounts receivable, less allowances (2020 - $2,303; 2019 - $1,842)	112,277	107,786
Contract assets	26,737	28,245
Inventories	81,182	80,544
Taxes receivable	3,219	3,427
Prepaid expenses	3,852	3,814
Other current assets	9,728	8,450
Total current assets	324,822	283,597
Property, plant and equipment, at cost	473,385	487,371
Accumulated depreciation	(268,609)	(265,729)
Net, property, plant and equipment	204,776	221,642
Operating lease right-of-use assets	22,266	23,116
Goodwill	82,668	133,912
Other intangible assets, net	109,181	115,577
Other assets, net	7,547	8,093
Total assets	751,260	785,937
Current liabilities:
Current portion of long-term debt	9,916	9,928
Accounts payable	93,020	73,426
Accrued payroll and other compensation	16,887	17,198
Other accrued liabilities	28,594	29,306
Total current liabilities	148,417	129,858
Long-term debt	278,240	262,713
Long-term operating lease liabilities	17,726	18,424
Deferred tax liabilities	31,799	34,561
Benefit plan liabilities	18,417	18,957
Other long-term liabilities	3,084	3,004
Commitments and Contingencies (Note 15)
Stockholders’ equity:
Preferred stock	0	0
Common stock	254	253
Capital in excess of par value	94,905	94,140
Retained earnings	284,208	340,629
Accumulated other comprehensive loss	(35,159)	(25,979)
Treasury stock, at cost	(90,631)	(90,623)
Total stockholders’ equity	253,577	318,420
Total liabilities and stockholders’ equity	$ 751,260	$ 785,937