Debtor-In-Possession Financial Information - Reorganization items, net (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017
Professional fees		$ 1.5
Legal fees		4.2
Write-off of unamortized debt issuance costs on the Senior Secured Notes		6.0
Reorganization items, net	$ 11.7	11.7
Real Industry
Professional fees		0.2
Legal fees		1.6
Reorganization items, net		1.8
Real Alloy
Professional fees		1.3
Legal fees		2.6
Write-off of unamortized debt issuance costs on the Senior Secured Notes		6.0
Reorganization items, net		9.9
Senior Secured Notes
Write-off of unamortized debt issuance costs on the Senior Secured Notes		$ 6.0