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Accumulated Other Comprehensive Loss (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Accumulated Other Comprehensive Loss [Abstract]
Unrealized gains (losses) on derivative instruments, tax	$ 0	$ (0.3)	$ (0.3)
Unrecognized actuarial net losses, tax	$ 26.0	$ 34.9	$ 69.7

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- Definition

Tax effect on the total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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No definition available.

+ Details

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- Definition

Tax effect on accumulated change 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 deferred hedging gains or losses.

+ References

No definition available.

+ Details

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- Details

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