Union Contracts (Details)	Sep. 30, 2014 employees
Middletown OH Works [Member]
Concentration Risk [Line Items]
Entity Number of Employees	1,640
Mountain State Carbon, LLC [Member]
Concentration Risk [Line Items]
Entity Number of Employees	220
Walbridge Tube [Member]
Concentration Risk [Line Items]
Entity Number of Employees	110
Ashland Works [Member]
Concentration Risk [Line Items]
Entity Number of Employees	820
Zanesville Works [Member]
Concentration Risk [Line Items]
Entity Number of Employees	130