Goodwill and Other Intangibles - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Goodwill [Line Items]
Changes in the goodwill balance during the period	$ 0
Goodwill	176,000,000		$ 176,000,000
Amortizable intangible assets related to property and casualty insurance acquisitions	31,000,000		34,000,000
Accumulated amortization	64,000,000		$ 62,000,000
Amortization of intangible assets	3,000,000	$ 3,000,000
Annuity subsidiaries \| Assets of discontinued annuity operations
Goodwill [Line Items]
Changes in the goodwill balance during the period	0
Goodwill	$ 31,000,000

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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 increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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