Major Customers (Details) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2021 USD ($) customer	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Revenue, Major Customer [Line Items]
Number of major customers | customer													5
Net sales	$ 73,168	$ 81,025	$ 80,461	$ 72,829	$ 60,654	$ 59,873	$ 37,806	$ 64,023	$ 56,122	$ 74,655	$ 81,247	$ 72,266	$ 307,483	$ 222,356	$ 284,290
Product sales
Revenue, Major Customer [Line Items]
Net sales	68,132	67,643	79,117	69,133	58,563	54,240	35,847	61,930	54,585	67,511	75,440	71,451	284,025	210,580	268,987
Tooling sales
Revenue, Major Customer [Line Items]
Net sales	$ 5,036	$ 13,382	$ 1,344	$ 3,696	$ 2,091	$ 5,633	$ 1,959	$ 2,093	$ 1,537	$ 7,144	$ 5,807	$ 815	23,458	11,776	15,303
BRP
Revenue, Major Customer [Line Items]
Net sales													37,813	21,931	20,982
BRP | Product sales
Revenue, Major Customer [Line Items]
Net sales													35,078	20,269	16,774
BRP | Tooling sales
Revenue, Major Customer [Line Items]
Net sales													2,735	1,662	4,208
Navistar
Revenue, Major Customer [Line Items]
Net sales													46,508	40,225	56,882
Navistar | Product sales
Revenue, Major Customer [Line Items]
Net sales													39,546	33,656	54,798
Navistar | Tooling sales
Revenue, Major Customer [Line Items]
Net sales													6,962	6,569	2,084
PACCAR
Revenue, Major Customer [Line Items]
Net sales													35,561	28,504	46,068
PACCAR | Product sales
Revenue, Major Customer [Line Items]
Net sales													33,545	27,997	44,543
PACCAR | Tooling sales
Revenue, Major Customer [Line Items]
Net sales													2,016	507	1,525
UFP
Revenue, Major Customer [Line Items]
Net sales													38,292	38,530	25,395
UFP | Product sales
Revenue, Major Customer [Line Items]
Net sales													38,292	38,530	25,395
UFP | Tooling sales
Revenue, Major Customer [Line Items]
Net sales													0	0	0
Volvo
Revenue, Major Customer [Line Items]
Net sales													35,977	25,724	48,749
Volvo | Product sales
Revenue, Major Customer [Line Items]
Net sales													35,854	23,538	48,487
Volvo | Tooling sales
Revenue, Major Customer [Line Items]
Net sales													123	2,186	262
Other
Revenue, Major Customer [Line Items]
Net sales													113,332	67,442	86,214
Other | Product sales
Revenue, Major Customer [Line Items]
Net sales													101,710	66,590	78,990
Other | Tooling sales
Revenue, Major Customer [Line Items]
Net sales													$ 11,622	$ 852	$ 7,224