Variable Interest Entities, Number of Entities Consolidated in the Period

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- Definition

Variable Interest Entities, Number of Entities Deconsolidated in the Period

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No definition available.

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- Definition

The amount of the variable interest entity's revenues consolidated into the statement of income, including interest income, net realized and unrealized gains (losses) on assets, and other income, net of the amount of the variable interest entity's expenses consolidated into the statement of income, including interest expense, net realized and unrealized gains (losses) on liabilities with and without recourse, and other expenses.

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- Definition

Variable Interest Entity, Number Matured

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- Definition

Variable Interest Entity, Number of Entities Consolidated

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- Definition

Variable Interest Entity, Non-Consolidated, Number of Policies Monitored

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- Definition

Variable Interest Entity, Number of Policies Monitored, Not Within the Scope of ASC 810

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- Definition

Variable Interest Entity, Number of Policies that Contain Provisions for Consolidation

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- Definition

Variable Interest Entity, Other Consolidated [Abstract]

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- Definition

Variable Interest Entity, Other Consolidated, Carrying Amount, Assets

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- Definition

Variable Interest Entity, Other Consolidated, Carrying Amount, Liabilities

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

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Amount of funds committed to investment company from investors.

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Amount of the fee for available but unused credit capacity under the credit facility.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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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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Variable Interest Entities - Narrative (Details)			1 Months Ended		3 Months Ended			9 Months Ended		12 Months Ended
Variable Interest Entities - Narrative (Details)	Aug. 26, 2020 USD ($)	Jun. 26, 2020 USD ($)	Sep. 30, 2020 USD ($) Entity policy	Sep. 30, 2020 EUR (€)	Sep. 30, 2020 USD ($) Entity policy	Sep. 30, 2020 USD ($) Entity policy	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) policy Entity	Sep. 30, 2019 USD ($) Entity	Dec. 31, 2019 USD ($) Entity policy	Aug. 26, 2020 EUR (€)
Variable Interest Entity [Line Items]
Net fair value gains and losses on FG VIEs are expected to reverse to zero at maturity of the VIE debt			$ 0		$ 0	$ 0		$ 0
Fair value gains (losses) on FG VIEs					0		$ 4,000,000	(8,000,000)	$ 42,000,000
Variable Interest Entity, Other Consolidated [Abstract]
Other consolidated VIE assets			95,000,000		95,000,000	95,000,000		95,000,000		$ 91,000,000
Other consolidated VIE liabilities			$ 12,000,000		$ 12,000,000	$ 12,000,000		$ 12,000,000		$ 12,000,000
Number of policies monitored \| policy			18,000		18,000	18,000		18,000
Number of policies monitored, not within the scope of ASC 810 \| policy			16,000		16,000	16,000		16,000
Number of policies that contain provisions for consolidation \| policy			84		84	84		84		90
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Total number of entities consolidated \| Entity			27		27	27		27		27
FG VIE matured in the period, number \| Entity								2	2
FG VIEs consolidated in the period \| Entity								2	1
FG VIEs deconsolidated in the period \| Entity									2
Fair value gains (losses) on FG VIEs					$ 0		4,000,000	$ (8,000,000)	$ 42,000,000
Variable Interest Entity, Primary Beneficiary \| Revolving Credit Facility [Member]
Variable Interest Entity [Line Items]
Maximum borrowing capacity		$ 175,000,000
Commitment percentage						70.00%
Commitment amount						$ 67,000,000
Proceeds from lines of credit						39,000,000
Variable Interest Entity, Primary Beneficiary \| Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR)
Variable Interest Entity [Line Items]
Basis spread on variable rate		1.75%
Variable Interest Entity, Primary Beneficiary \| Line of Credit [Member]
Variable Interest Entity [Line Items]
Maximum borrowing capacity	$ 164,000,000										€ 140,000,000
Commitment percentage			70.00%	70.00%
Commitment amount			$ 8,000,000	€ 7,000,000
Proceeds from lines of credit			8,000,000	€ 7,000,000
Variable Interest Entity, Primary Beneficiary \| Line of Credit [Member] \| EURIBOR
Variable Interest Entity [Line Items]
Basis spread on variable rate	1.70%
Variable Interest Entity, Primary Beneficiary \| Line of Credit [Member] \| Base Rate
Variable Interest Entity [Line Items]
Basis spread on variable rate	0.50%
Residential Mortgage Backed Securities and Other Insurance Products \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Change in the instrument specific credit risk of the VIEs' assets					14,000,000		$ 7,000,000	(2,000,000)	$ 42,000,000
Future Equity Investments \| Maximum
Variable Interest Entity [Line Items]
Long-term purchase commitment, amount								100,000,000
Committed capital								12,000,000
Equity Method Investments \| AGL Subsidiaries \| AssuredIM \| Maximum
Variable Interest Entity [Line Items]
Long-term purchase commitment, amount										$ 79,000,000
Long-term purchase commitment fair value										$ 77,000,000
Consolidated Investment Vehicles
Variable Interest Entity [Line Items]
Fair value gains (losses) on FG VIEs								(8,000,000)
Consolidated Investment Vehicles \| Foreign Exchange Forward
Variable Interest Entity [Line Items]
Collateral posting requirement			3,000,000		3,000,000	3,000,000		3,000,000
Consolidated Investment Vehicles \| Average \| Foreign Exchange Forward
Variable Interest Entity [Line Items]
Collateral posting requirement			$ 2,000,000		$ 2,000,000	$ 2,000,000		$ 2,000,000