Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
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	$ 43	$ 51	$ 117
Liabilities assumed			34
Redemption, related party debt	0	0	140
Notes due to related parties	140	140
Liabilities for collateral received reported in other liabilities and accrued expenses	517	539	545
Obligations to return cash collateral for over-the-counter ("OTC") derivatives reported in other liabilities and accrued expenses or other investments	8	3	5
Net change in proceeds managed
Net change in fixed income securities	94	149	(277)
Net change in short-term investments	(77)	(142)	277
Operating cash flow provided	17	7	0
Net change in cash	0	1	0
Net change in proceeds managed	17	8	0
Net change in liabilities
Liabilities for collateral, beginning of year	(542)	(550)	(550)
Liabilities for collateral, end of year	(525)	(542)	(550)
Operating cash flow (used) provided	$ (17)	(8)	0
Other
Debt Instrument [Line Items]
Decrease in notes receivable, related parties		325
ALIC Re \| Affiliate
Debt Instrument [Line Items]
Redemption, related party debt		$ 325
4.14% Surplus Note, due 2036 \| ALIC Re \| Kennett
Debt Instrument [Line Items]
Notes due to related parties			$ 50

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 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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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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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 liabilities assumed in noncash investing or financing activities.

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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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