Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred Tax Liabilities, Other	$ 0.0	$ 120.6
Preferred Stock, Shares Authorized	5,000,000	5,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	90,000,000	90,000,000
Common Stock, Shares, Issued	22,291,180	21,197,164
Common Stock, Shares, Outstanding	18,053,747	17,607,251
Treasury Stock, Shares	4,237,433	3,589,913
Union VEBA
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred Tax Liabilities, Other	$ 0.0	$ 127.0