Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 72,289	$ 53,911
Accounts receivable, net of allowance for doubtful accounts of $1,171 and $1,638 at December 31, 2019 and 2018, respectively	76,092	91,939
Inventories	107,276	120,068
Unbilled receivables	16,318	15,799
Other current assets	11,206	8,792
Total current assets	283,181	290,509
Property, plant and equipment, net	41,943	43,932
Right-of-use assets	18,504
Intangible assets, net	72,364	62,689
Goodwill	21,993	19,817
Deferred income taxes	3,731	496
Other assets	27,201	26,081
Total assets	468,917	443,524
Current liabilities:
Accounts payable	44,169	56,171
Accrued expenses	26,918	32,290
Current maturities of long-term debt	5,489	2,508
Operating lease liability, current	7,377
Other current liabilities	6,265	15,061
Total current liabilities	90,218	106,030
Long-term liabilities:
Long-term debt	138,215	111,705
Operating lease liability, long-term	11,751
Liability for uncertain tax positions	26,901	27,553
Minimum pension obligation and unfunded pension liability	21,545	18,683
Deferred income taxes	1,726	1,161
Other long-term liabilities	10,510	1,922
Total liabilities	300,866	267,054
Commitments and contingencies
Stockholders' equity:
Preferred stock, no par value, 1,000,000 shares authorized; none issued
Additional paid-in capital	33,826	31,387
Retained earnings	157,063	168,695
Accumulated other comprehensive loss	(24,065)	(24,838)
Total stockholders' equity	168,051	176,470
Total liabilities and stockholders' equity	468,917	443,524
Common Class A [Member]
Stockholders' equity:
Common stock	214	217
Common Class B [Member]
Stockholders' equity:
Common stock	$ 1,013	$ 1,009