Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Non-cash modifications of certain mortgage loans, fixed income securities, limited partnerships and other investments, as well as mergers completed with equity securities	$ 67	$ 43	$ 51
Redemption, related party debt	215	0	0
Notes due to related parties	214	140
Liabilities for collateral received reported in other liabilities and accrued expenses	522	517	539
Obligations to return cash collateral for over-the-counter ("OTC") derivatives reported in other liabilities and accrued expenses or other investments	8	8	3
Net change in proceeds managed
Net change in fixed income securities	28	94	149
Net change in short-term investments	(33)	(77)	(142)
Operating cash flow (used) provided	(5)	17	7
Net change in cash	0	0	1
Net change in proceeds managed	(5)	17	8
Net change in liabilities
Liabilities for collateral, beginning of year	(525)	(542)	(550)
Liabilities for collateral, end of year	(530)	(525)	(542)
Operating cash flow provided (used)	$ 5	$ (17)	(8)
Other
Debt Instrument [Line Items]
Decrease in notes receivable, related parties			325
ALIC Re \| Affiliate
Debt Instrument [Line Items]
Redemption, related party debt			$ 325

The net operating cash flow provided by (used in) the net change in liabilities for collateral.

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The net operating cash flow provided or used related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The net change in cash from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The net change in the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The net change in short-term investments from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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Net Change in Fixed Income Term Investments of Proceeds Managed Collateral

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The liability to return cash and securities received as collateral in conjunction with securities lending and over-the-counter derivatives.

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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.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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The increase (decrease) during the reporting period in the amount owed to the reporting entity in the form of loans and obligations (generally evidenced by promissory notes) made to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The fair value of collateral received by the entity associated with securities borrowed that must be returned if the counterparty fulfills its obligations. It appears on the balance sheet as a liability and has a corresponding asset that appears on the balance sheet called Securities Received as Collateral.

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Value of investments transferred from the entity's investments in noncash transactions.

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