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Contractual interest rate for funds borrowed, under the debt agreement.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of premium receivables under financial guarantee insurance contracts.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount of funds committed to investment company from investors.

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Amount of expected guaranteed benefits in excess of the projected account balances for minimum guaranteed benefit contracts, as of the balance sheet date.

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Percentage of risk reinsured on insurance products per entity policy.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Financial instruments issued by insurance entities (surplus notes) that are includable in surplus for statutory accounting purposes as prescribed or permitted by state laws and regulations that are liabilities of the issuer.

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Accrued interest payment on surplus notes issued by VIE. The interest is eliminated in consolidation with the primary beneficiary.

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Collateral Held in Supplement Trust

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Represents the percentage ceded under quota share reinsurance agreement.

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Percent change in discounted future cash flows

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Municipal Bond Guarantee - Narrative (Details) - USD ($) $ in Millions		1 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
	Jan. 01, 2014	Jan. 31, 2020	Nov. 30, 2018	Apr. 30, 2018	Mar. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2012	Dec. 31, 2024	Jun. 30, 2020	Sep. 30, 2019	Dec. 31, 2017	Dec. 31, 2013	Jul. 31, 2012
Guarantor Obligations [Line Items]
Percent change in discounted future cash flows						10.00%
HG Global
Guarantor Obligations [Line Items]
Collateral held in supplement trust						$ 813.8	$ 786.7
Interest receivable						$ 159.8	162.7
BAM
Guarantor Obligations [Line Items]
Surplus notes							457.6				$ 409.7
Interest receivable							$ 7.5				4.7
HG Global
Guarantor Obligations [Line Items]
Capital invested									$ 594.5
Surplus notes															$ 503.0
Cash and Fixed Income Securities															100.0
Percent over a target trust balance						102.00%
Supplement Trust Target						$ 603.0
HG Global \| Preferred Stock
Guarantor Obligations [Line Items]
Ownership interest (as a percent)						96.90%	96.60%
HG Global \| Common equity securities
Guarantor Obligations [Line Items]
Ownership interest (as a percent)						88.40%	89.60%
HG Global \| Surplus Note
Guarantor Obligations [Line Items]
Surplus notes															503.0
Percentage of par value of policy reinsured						15.00%
HG Global \| Series B BAM Surplus Note
Guarantor Obligations [Line Items]
Surplus notes															300.0
HG Global \| Series A BAM Surplus Note
Guarantor Obligations [Line Items]
Surplus notes													$ 203.0		$ 203.0
HG Global \| BAM
Guarantor Obligations [Line Items]
Term of Agreement		10 years
HG Global \| BAM \| Maximum
Guarantor Obligations [Line Items]
Aggregate losses on ceded business		$ 75.0
HG Global \| Non-controlling interest
Guarantor Obligations [Line Items]
Capital invested									$ 14.5
BAM
Guarantor Obligations [Line Items]
Number of years of change in interest rate								3 years
Municipal bond outstanding principal						$ 70,954.1	$ 62,250.5					$ 1,100.0
Additional municipal bond guarantee											$ 36.9
BAM \| Supplemental Trust
Guarantor Obligations [Line Items]
Repayments of Unsecured Debt					$ 47.9
Accrued Interest Payment on Surplus Notes					0.9
BAM \| Surplus Note
Guarantor Obligations [Line Items]
Percentage of risk premium ceded						60.00%
Derivative, fixed interest rate (as a percent)														8.00%
Repayments of Unsecured Debt					65.0
Accrued Interest Payment on Surplus Notes					$ 16.2
BAM \| US Treasury (UST) Interest Rate \| Surplus Note
Guarantor Obligations [Line Items]
Basis spread on variable rate	3.00%					4.60%	5.70%
BAM \| Forecast \| Surplus Note
Guarantor Obligations [Line Items]
Derivative, fixed interest rate (as a percent)										8.00%
BAM \| Fidus Re Ltd.
Guarantor Obligations [Line Items]
Secured Debt				$ 100.0
Collateralized financial guarantee, term				12 years
Collateral financial guarantee, callable term					5 years
Aggregate losses on ceded business				$ 165.0
Premium receivable, Premium expected to be collected				100.0
Municipal bond outstanding principal			$ 2,200.0
Percentage of quota share reinsurance agreement			100.00%
BAM \| Fidus Re Ltd. \| Maximum
Guarantor Obligations [Line Items]
Aggregate losses on ceded business				$ 276.1
Fidus Re Ltd. \| BAM
Guarantor Obligations [Line Items]
Losses above retention, percentage of liability				90.00%