Supplementary Balance Sheet Information - Narrative (Details) $ in Thousands		1 Months Ended	3 Months Ended
	Sep. 06, 2019	Apr. 30, 2019 USD ($) property_purchased property	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Sale Leaseback Transaction [Line Items]
Manufacturing facilities purchased		3
Purchase of plants | $		$ 5,200	$ 158	$ 387
KBS Builders
Sale Leaseback Transaction [Line Items]
Manufacturing facilities purchased		2
Number of properties leasedback | property		3
North Country Steel Inc.
Sale Leaseback Transaction [Line Items]
Lease period	5 years