The gross amount of life insurance in force as of the balance sheet date.

No definition available.

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Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the carrying amount of the investments held by trust.

+ References

No definition available.

+ Details

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Namespace Prefix:	all_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of life insurance issued and outstanding ceded to other entity, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column C
-Subsection 17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column C))
-URI http://asc.fasb.org/extlink&oid=120401096&loc=d3e574992-122915

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before valuation allowance recoverable 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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
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- Details

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- Details

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Reinsurance and Indemnification - Other Reinsurance Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reinsurance Retention Policy [Line Items]
Reinsurance recoverables	$ 66	$ 73
Life insurance in force ceded to unaffiliated reinsurers	67,319	74,021	$ 81,186
Allstate Annuities
Reinsurance Retention Policy [Line Items]
Gross life insurance in force	425,440
Life insurance in force ceded to unaffiliated reinsurers	67,320
Prudential \| Allstate Annuities
Reinsurance Retention Policy [Line Items]
Reinsurance recoverables	1,280	1,290
Citigroup Subsidiaries and Scottish Re \| Operating costs and expenses \| Allstate Annuities
Reinsurance Retention Policy [Line Items]
Reinsurance recoverables	99	$ 112
Lincoln Benefit Life Company
Reinsurance Retention Policy [Line Items]
Investments held by trust	$ 6,290