Business Acquisitions (Intangible Assets Acquired) (Details) - USAA-IMCO [Member] $ in Millions	May 26, 2020 USD ($)
Business Acquisition [Line Items]
Estimated Fair Value	$ 1,118
Customer relationships [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 962
Weighted-Average Estimated Useful Life (years)	18 years
Brokerage referral agreement [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 151
Weighted-Average Estimated Useful Life (years)	20 years
Initial period	5 years
Renewal period	1 year
Royalty-free license [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 5
Weighted-Average Estimated Useful Life (years)	7 years

Acquired Finite-lived Intangible Asset, Weighted-Average, Renewal Period

No definition available.

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- Definition

Weighted average period before the next renewal or extension for intangible assets with renewal or extension terms, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Details

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- Details

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