Enviromental Obligations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Recorded Recoveries [Roll Forward]
Expected recoveries recorded, beginning	$ 72.1		$ 82.6
Increase in Recoveries	9.2		7.2
Cash Received	24.8		17.7
Expected recoveries recorded, ending	56.5		72.1		82.6
Accrual for Environmental Loss Contingencies, Balance Sheet Classification [Abstract]
Environmental reserves, current, net of recoveries	29.5	[1]	15.8	[1]
Environmental reserves, long-term continuing and discontinued, net of recoveries	175.2	[2]	200.2	[2]
Total environmental reserves, net of recoveries	204.7		216.0		226.9		224.9
Continuing operations	6.2	[3]	5.8	[3]	3.1	[3]
Discontinued operations	37.3	[4]	20.4	[4]	25.4	[4]
Environmental Provision, Net of Recoveries recorded to Other Assets	43.5		26.2		28.5
Accrual for Environmental Loss Contingencies, Increase (Decrease) for Revision in Estimates	48.2	[5]	31.2	[5]	45.2	[5]
Environmental Cost Recognized, Recovery Credited to Expense	(4.7)	[6]	(5.0)	[6]	(16.7)	[6]
Days after expiration to file notice to dispute	15 days
Front Royal [Member]
Accrual for Environmental Loss Contingencies, Balance Sheet Classification [Abstract]
Total environmental reserves, net of recoveries	25.6		41.2
Pocatello [Member]
Accrual for Environmental Loss Contingencies, Balance Sheet Classification [Abstract]
Total environmental reserves, net of recoveries	61.3		61.7
Tribal Permit Fee	1.5
Tribal Court Decision on Permit Fees	9.0
Middleport [Member]
Accrual for Environmental Loss Contingencies, Balance Sheet Classification [Abstract]
Total environmental reserves, net of recoveries	41.7		42.4
Properties	200
Clean up standard parts per million	20
Environmental Liabilities, Continuing and Discontinued [Member]
Recorded Recoveries [Roll Forward]
Expected recoveries recorded, beginning	20.5		24.3
Increase in Recoveries	4.5		2.2
Cash Received	4.0		6.0
Expected recoveries recorded, ending	21.0		20.5
Other Assets [Member]
Recorded Recoveries [Roll Forward]
Expected recoveries recorded, beginning	51.6	[7]	58.3	[7]
Increase in Recoveries	4.7		5.0
Cash Received	20.8		11.7
Expected recoveries recorded, ending	$ 35.5	[7]	$ 51.6	[7]

[1] “Current” includes only those reserves related to continuing operations. These amounts are included within “Accrued and other liabilities” on the consolidated balance sheets.

[2] These amounts are included in "Environmental liabilities, continuing and discontinued" on the consolidated balance sheets.

[3] Recorded as a component of “Restructuring and other charges (income)” on our consolidated statements of income. See Note 7.

[4] Recorded as a component of “Discontinued operations, net" on our consolidated statements of income. See Note 9.

[5] See above roll forward of our total environmental reserves as presented on our consolidated balance sheets.

[6] Represents certain environmental recoveries. See Note 21 for details of Other assets as presented on our consolidated balance sheets.

[7] The amounts are included within “Prepaid and other current assets" and "Other assets". See Note 21 for more details.