Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net (loss) income from continuing operations		$ (45,677)	$ 3,471
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustment		(5,639)	(920)
Unrealized gain on cash flow hedges, net of tax expense of $0 and $44, respectively		1,755	131
Cash flow hedges reclassified to earnings, net of tax expense of $0 and $235, respectively		159	703
Pension and post-retirement benefit plans benefit, net of tax benefit of $357 and $422, respectively		1,352	1,436
Reclassification of pension liability adjustments to earnings, net of tax expense of $6 and benefit of $19, respectively*	[1]	53	55
Total comprehensive (loss) income from continuing operations		(47,997)	4,876
Less comprehensive loss attributable to noncontrolling interest:
Net loss attributable to noncontrolling interest		(113)	(83)
Foreign currency translation adjustment		15	(18)
Amounts attributable to noncontrolling interest		(98)	(101)
Comprehensive (loss) income from continuing operations attributable to L.B. Foster Company		$ (47,899)	$ 4,977

[1] Reclassifications out of Accumulated other comprehensive loss for pension obligations are reflected in Selling and administrative expense.