New Accounting Pronouncements (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Dec. 15, 2011
Accounting Policies [Abstract]
Capitalized expenses, not deferrable under new guidance		$ 2.5
Effect on 2011 pretax operating income from change in guidance (as a percentage)	3.00%

New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results, Percentage

No definition available.

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Period Type:	duration