Adoption of New Accounting Pronouncements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Jan. 01, 2010
Decrease in deferred policy acquisition costs due to the adoption of new accounting guidance	$ 420
Decrease in deferred income tax liabilities due to the adoption of new accounting guidance	147
Decrease in shareholders' equity due to the adoption of new accounting guidance	$ 273

The decrease in deferred policy acquisition costs due to the adoption of new accounting guidance related to the accounting for costs associated with acquiring or renewing insurance contracts.

No definition available.

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Data Type:	xbrli:monetaryItemType
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