Investments (Unconsolidated Variable Entities) Narrative (Details) - RMBS $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Variable Interest Entity [Line Items]
Proceeds from securitization of loan held for investment carrying value	$ 443	$ 443
Proceeds from Securitizations of Loans Held-for-investment	467	467
Gain (Loss) on Securitization of Financial Assets	24	24
Transfers of Financial Assets Accounted for as Sale, Initial Fair Value of Assets Obtained as Proceeds	$ 133	$ 133

Proceeds from securitization of loan held for investment carrying value

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- Definition

A gain (loss) realized on a transfer, accounted for as a sale, of all or a portion of financial assets in which the transferor surrenders control and receives consideration other than a beneficial interest in the assets transferred. Reflects the amount of sales proceeds in excess of, or deficient from, the sum of the carrying amounts of transferred financial assets plus transaction costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The cash inflow from the securitization of loans held for investment. Securitization is the structured process whereby interests in loans and other receivables are packaged, underwritten, and sold in the form of asset-backed securities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

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- Definition

Represents the initial fair value recorded for assets received on transfer of financial assets in a securitization, asset-backed financing arrangement, or a similar transfer which transaction is recognized as a sale of the transferred financial assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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