Investments (Schedule Of Components Of Restricted Assets) (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Investments [Line Items]
Total restricted assets	$ 16,072	$ 15,836
Asset Pledged as Collateral without Right
Investments [Line Items]
Trust funds	8,194	8,120
Deposits with U.S. regulatory authorities	2,337	2,345
Deposits with non-U.S. regulatory authorities	3,115	2,959
Assets pledged under repurchase agreements	1,565	1,527
Other pledged assets	$ 861	$ 885

[Line Items] for This table lists the investments. The line items identify information about all investments.

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- Definition

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

+ References

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Restricted assets that are deposits with US regulatory authorities.

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- Definition

The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(b))
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Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(a))
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Amount of current assets that are pledged or subject to withdrawal restrictions, classified as other.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
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