Investment Holding Level 4 Other than Temporary Impairment, Credit Losses Recognized in Earnings (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
May 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Jan. 01, 2018
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ 0	$ 6	$ 4
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held	(70)	(6)	(4)	$ (88)
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	0	(6)	(4)
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Securities Sold	17	0	6
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Cash Flows	$ 1	$ 0	$ 0

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

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Period Type:	duration

- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL6284393-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL6284393-111563

+ 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

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held due to increases in cash flows expected to be collected and recognized over the remaining life of the security.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

No definition available.

+ Details

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