Derivatives (Details) (Cash Flow Hedging [Member], USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Commodity Futures Contracts [Member]
Amounts related to cash flow hedges
Gains (loss) included in AOCI, net of tax	$ (3.7)	$ (11.7)
Provision(Benefit) for income taxes	2.1	6.7
Interest Rate Swap [Member]
Amounts related to cash flow hedges
Gains (loss) included in AOCI, net of tax	1.8	2.3
Provision(Benefit) for income taxes	$ (1.1)	$ (1.3)

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 26

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