Goodwill and Other Intangible Assets (Narrative) (Details)	3 Months Ended	4 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) reporting_unit	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Aug. 31, 2023 USD ($)
Finite-Lived Intangible Assets [Line Items]
AEC reporting units | reporting_unit	2
Goodwill impairment charges	$ 0		$ 0
Amortized intangible assets, gross		$ 87,100,000	87,100,000
Amortized intangible assets, accumulated amortization		48,500,000	48,500,000
Amortization of intangible assets			4,452,000	$ 4,842,000
Cost of Sales
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets			400,000	800,000	$ 3,000,000
Selling, General and Administrative Expenses
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets			4,100,000	$ 4,000,000	$ 4,200,000
Heimbach
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets						$ 14,901,000
Amortization of intangible assets			$ 300,000
Heimbach | AEC Technology
Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangibles						$ 8,900,000
Finite-lived intangible assets, useful life						9 years
Amortization of intangible assets		$ 300,000
Heimbach | AEC Tradema
Finite-Lived Intangible Assets [Line Items]
Acquired indefinite-lived intangible assets						$ 6,000,000