Investments - Mortgage Loans, Net (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans, net of allowances	$ 14,591	$ 14,306
Commercial mortgage loans
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans, before allowance for credit losses	11,390	10,515
Mortgage loan valuation allowance	(232)	(10)
Mortgage loans, net of allowances	11,158	10,505
Commercial mortgage loans \| Commercial mortgage loans
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans, before allowance for credit losses	11,194	10,422
Mortgage loans, net of allowances		10,412
Commercial mortgage loans \| Commercial mortgage loans under development
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans, before allowance for credit losses	196	93
Residential mortgage loans
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans, before allowance for credit losses	4,169	4,455
Mortgage loan valuation allowance	(96)	(1)
Mortgage loans, net of allowances	4,073	4,454
Investments including related party
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans, net of allowances	$ 15,231	$ 14,959

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 310
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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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