Reinsurance - Schedule of Novated Balances (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Schedule of Novated Balances [Line Items]
Reinsurance recoverable	$ 4,863	$ 5,534
Novation [Member]
Schedule of Novated Balances [Line Items]
Interest sensitive contract liabilities	407
Future policy benefits	305
Funds withheld liability	347
Investments	320
Policy loans	38
Reinsurance recoverable	674
Other assets	$ 27

[Line Items] for Schedule of Novated Balances [Table]

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Amount of funds held as security for payments to be received under reinsurance contracts.

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Amount, before effect of reinsurance, of present value of future benefit to be paid to or on behalf of policyholder and related expense less present value of future net premium receivable under insurance contract.

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Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of assets classified as other.

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Amount of liability due to policyholder for deposit held under long-duration contract issued by insurance entity.

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Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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