Significant Risks and Uncertainties - Narrative (Details) $ in Millions	Sep. 30, 2018 USD ($) issuer	Dec. 31, 2017 USD ($) issuer
Concentration Risk [Line Items]
Exposure of FGL's invested assets	33.00%
Number of issuers in investment \| issuer	112
Wilton Reassurance Company
Concentration Risk [Line Items]
Net amount recoverable	$ 1,546
All Financial Instruments
Concentration Risk [Line Items]
FGL's investment securities in the banking industry	$ 2,642
Exposure of FGL's invested assets	11.00%
Single Issuer
Concentration Risk [Line Items]
FGL's investment securities in the banking industry	$ 119
Exposure of FGL's invested assets	1.00%
Banking Industry \| All Financial Instruments
Concentration Risk [Line Items]
Investment securities held by subsidiaries subject to specialized industry accounting principles, amortized cost	$ 2,760
Predecessor
Concentration Risk [Line Items]
Exposure of FGL's invested assets	10.00%	10.00%
Number of issuers in investment \| issuer	0	0
Predecessor \| All Financial Instruments
Concentration Risk [Line Items]
FGL's investment securities in the banking industry		$ 2,851
Exposure of FGL's invested assets		12.00%
Predecessor \| Single Issuer
Concentration Risk [Line Items]
FGL's investment securities in the banking industry		$ 155
Exposure of FGL's invested assets		1.00%
Predecessor \| Banking Industry \| All Financial Instruments
Concentration Risk [Line Items]
Investment securities held by subsidiaries subject to specialized industry accounting principles, amortized cost		$ 2,850

Investment Securities Held by Subsidiaries Subject to Specialized Industry Accounting Principles at Amortized Cost

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- Definition

Investment Securities Held by Subsidiaries Subject to Specialized Industry Accounting Principles at Fair Value

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- Definition

Number Of Issuers In Investment

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Percentage of investments fair value in relation to invested assets portfolio.

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The net amount (to the extent disclosed within this portion of the income statement) by which an insurance settlement exceeds incremental costs incurred from the event causing an interruption of business, plus the insurance award for earnings lost from the event, such as a natural catastrophe, explosion or fire.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64839914&loc=d3e16285-107787

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