Employee Retirement Plans and Postretirement Benefits Target And Actual Allocations (Details)	12 Months Ended
	Dec. 31, 2014
Equity funds
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations (as a percent)	30.00%
Actual allocations (as a percent)	28.80%
Fixed Income Funds [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations (as a percent)	48.30%
Actual allocations (as a percent)	46.60%
Hedge funds of funds
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations (as a percent)	7.50%
Actual allocations (as a percent)	6.10%
Real estate funds
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations (as a percent)	4.40%
Actual allocations (as a percent)	5.30%
Other assets
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations (as a percent)	9.80%
Actual allocations (as a percent)	13.20%