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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

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Reinsurance (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Ceded Credit Risk [Line Items]
Reinsurance ACL and deposit assets		$ 192
Trading securities	$ 4,019		$ 4,673
Fixed maturity AFS securities	102,606		105,200
Mortgage loans on real estate	16,791		16,339
Derivative investments	4,417		1,911
Other investments	4,765		2,994
Cash and invested cash	6,202		2,563	$ 1,593	$ 2,345
Accrued investment income	1,185		1,148
Equity securities	83		103
Athene Holding Ltd. [Member]
Ceded Credit Risk [Line Items]
Deposit assets	6,300		$ 6,600
Reserves associated with modified coinsurance reinsurance arrangements	6,200
Letter of credit	188
Trading securities	3,000
Fixed maturity AFS securities	1,800
Derivative investments	49
Other investments	111
Cash and invested cash	378
Accrued investment income	48
Equity securities	14
Athene Holding Ltd. [Member] \| Over-Collateralization [Member]
Ceded Credit Risk [Line Items]
Reserves associated with modified coinsurance reinsurance arrangements	175
Athene Holding Ltd. [Member] \| Commercial Mortgage Loans [Member]
Ceded Credit Risk [Line Items]
Mortgage loans on real estate	$ 765