Business Segments (Assets by Segment) (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Assets	$ 411,280	$ 566,660
Rail Products and Services [Member]
Segment Reporting Information [Line Items]
Assets	155,657	241,222
Construction Products [Member]
Segment Reporting Information [Line Items]
Assets	83,061	86,335
Tubular and Energy Services [Member]
Segment Reporting Information [Line Items]
Assets	103,976	216,715
Unallocated Corporate Assets [Member]
Segment Reporting Information [Line Items]
Assets	$ 68,586	$ 22,388