CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 43,416	$ 49,237
Accounts receivable, less allowances (2019 - $2,087; 2018 - $1,440)	147,392	144,938
Contract assets	21,566	23,040
Inventories	88,232	84,465
Taxes receivable	2,745	2,912
Prepaid expenses	5,190	4,707
Other current assets	8,474	7,779
Total current assets	317,015	317,078
Property, plant and equipment, at cost	473,943	458,075
Accumulated depreciation	(255,736)	(244,706)
Net, property, plant and equipment	218,207	213,369
Operating lease right-of-use assets	27,070	0
Goodwill	197,796	196,963
Other intangible assets, net	126,696	136,604
Other assets, net	9,650	8,672
Total assets	896,434	872,686
Current liabilities:
Current portion of long-term debt	10,001	10,172
Accounts payable	81,053	73,265
Accrued payroll and other compensation	15,985	16,621
Deferred revenue	3,446	6,990
Other accrued liabilities	21,382	14,298
Total current liabilities	131,867	121,346
Long-term debt	289,673	314,641
Long-term operating lease liabilities	22,006	0
Deferred tax liabilities	37,640	39,265
Benefit plan liabilities	22,849	22,795
Other long-term liabilities	5,294	5,364
Commitments and Contingencies (Note 16)
Stockholders’ equity:
Preferred stock	0	0
Common stock	253	253
Capital in excess of par value	92,297	90,851
Retained earnings	408,086	411,325
Accumulated other comprehensive loss	(23,007)	(42,685)
Treasury stock, at cost	(90,524)	(90,469)
Total stockholders’ equity	387,105	369,275
Total liabilities and stockholders’ equity	$ 896,434	$ 872,686