Benefits 2 Narrative Parentheticals (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Compensation and Retirement Disclosure [Abstract]
Pretax curtailment gain	$ 74.6
Noncurrent refund liability	59.3
Curtailment recognition	$ 15.3

The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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+ Details