Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant & Equipment
Total	$ 183,500	$ 174,553
Less accumulated depreciation	(107,603)	(100,501)
Property, plant and equipment, net	75,897	74,052
Purchase commitments for capital expenditures in progress	5,315	677
Accounts payable	22,695	16,994
Depreciation expense	9,181	8,659	$ 8,187
Accounts Payable, Current
Property, Plant & Equipment
Purchase commitments for capital expenditures in progress	329	145
Land and land improvements
Property, Plant & Equipment
Total	6,009	6,009
Buildings
Property, Plant & Equipment
Total	43,901	43,545
Machinery and equipment
Property, Plant & Equipment
Total	124,760	121,382
Tools, dies and patterns
Property, Plant & Equipment
Total	2,225	2,195
Additions in progress
Property, Plant & Equipment
Total	$ 6,605	$ 1,422

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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