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Adoption of Accounting Pronouncements (Narrative) (Details) (USD $) In Millions, except Per Share data	Sep. 30, 2011
Adoption of Accounting Pronouncements [Abstract]
Potential after-tax impact on stockholders' equity	$ 55
Potential after-tax impact on book value per share	$ 1

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- Definition

Potential after-tax impact on the entity's stockholders' book value per share as a result of the adoption of the accounting pronouncement.

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- Definition

Potential after-tax impact on the entity's stockholders' equity as a result of the adoption of the accounting pronouncement.

+ Details

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- Details

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