CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income (loss)		$ 1,299	$ (45,677)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment		2,428	(5,639)
Unrealized (loss) gain on cash flow hedges, net of tax expense of $0		(704)	1,755
Cash flow hedges reclassified to earnings, net of tax expense of $0		0	159
Pension and post-retirement benefit plans benefit, net of tax benefit of $0 and $357, respectively		152	1,352
Reclassification of pension liability adjustments to earnings, net of tax expense of $0 and benefit of $6, respectively*	[1]	39	53
Total comprehensive income (loss)		3,214	(47,997)
Less comprehensive loss attributable to noncontrolling interest:
Net loss attributable to noncontrolling interest		(165)	(113)
Foreign currency translation adjustment		29	15
Amounts attributable to noncontrolling interest		(136)	(98)
Comprehensive income (loss) attributable to L.B. Foster Company		$ 3,350	$ (47,899)

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