Investments (Schedule Of Components Of Restricted Assets) (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Trust funds	$ 14,938	$ 13,880
Deposits with U.S. regulatory authorities	2,325	2,203
Deposits with non-U.S. regulatory authorities	2,170	2,191
Assets pledged under repurchase agreements	1,472	1,461
Other pledged assets	371	435
Total restricted assets	$ 21,276	$ 20,170

Restricted assets that are deposits with non-US regulatory authorities.

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- Definition

Restricted assets that are deposits with US regulatory authorities.

+ References

No definition available.

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- Definition

Restricted assets that are other pledged assets.

+ References

No definition available.

+ Details

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- Definition

Restricted assets that are trust funds.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for repurchase agreements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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- Definition

Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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No definition available.

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