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Fair Value Measurements - Summary of Carrying Amount and Fair Value of Ambac's Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	$ 1,923,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	1,000	$ 0	$ 1,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	31,000	31,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	90,000	106,000
Financial assets:
Derivative assets	31,000	28,000
Other assets	0
Long-term Debt	497,000	639,000
Financial liabilities:
Derivative liabilities	44,000	38,000
Equity Securities Excluded From Fair Value Table	12,000	12,000
Debt Securities, Available-for-sale, Amortized Cost	1,983,000	2,041,000
Debt Securities, Available-for-Sale, Current	1,923,000	1,966,000
Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	1,494,000	1,395,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	1,000	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	31,000	31,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	90,000	106,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	1,554,000	1,469,000
Fixed Income Investments And Other Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	1,862,000	1,902,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	1,000	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	31,000	31,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	90,000	106,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	1,922,000	1,977,000
Commercial Mortgage Backed Securities [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Short-term Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	367,000	507,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	367,000	507,000
Asset-backed Securities [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	223,000	224,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,000	2,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	5,000	5,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	226,000	227,000
Collateralized Debt Obligations [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	137,000	137,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3,000	4,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	140,000	141,000
Residential Mortgage-Backed Securities [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	240,000	238,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	1,000	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	26,000	28,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	16,000	19,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	231,000	230,000
US Government Debt Securities [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	63,000	65,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3,000	4,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	66,000	68,000
Debt Security, Government, Non-US [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	79,000	76,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	8,000	9,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	86,000	85,000
Corporate Debt Securities [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	679,000	598,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,000	1,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	54,000	63,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	732,000	659,000
Municipal Bonds [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	57,000	43,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,000	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,000	2,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	58,000	44,000
Collateralized Mortgage Backed Securities [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	15,000	15,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	15,000	15,000
Total Fair Value [Member]
Financial assets:
Cash	40,000	44,000
Reported Value Measurement [Member]
Financial assets:
Other investments	65,000	61,000
Cash	40,000	44,000
Loans	2,000	10,000
Total financial assets	7,056,000	6,726,000
Financial liabilities:
Liabilities for net financial guarantees written	318,000	159,000
Long-term debt	935,000	1,065,000
Total financial liabilities	5,531,000	5,418,000
Reported Value Measurement [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	367,000	507,000
Reported Value Measurement [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	557,000	568,000
Reported Value Measurement [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities	44,000	38,000
Reported Value Measurement [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Financial assets:
Derivative assets	30,000	27,000
Reported Value Measurement [Member] | Warrants [Member]
Financial assets:
Derivative assets	1,000	1,000
Level 1 [Member]
Financial assets:
Cash	38,000	43,000
Total financial assets	922,000	833,000
Financial liabilities:
Liabilities for net financial guarantees written	0	0
Long-term debt	0	0
Total financial liabilities	0	0
Level 1 [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	359,000	506,000
Level 1 [Member] | Loans Receivable [Member]
Financial assets:
Loans	0	0
Level 1 [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	65,000	61,000
Level 1 [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities	0	0
Level 1 [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Financial assets:
Derivative assets	0	0
Level 1 [Member] | Warrants [Member]
Financial assets:
Derivative assets	0	0
Level 2 [Member]
Financial assets:
Cash	2,000	1,000
Total financial assets	1,669,000	1,615,000
Financial liabilities:
Liabilities for net financial guarantees written	0	0
Long-term debt	764,000	864,000
Total financial liabilities	4,918,000	4,942,000
Level 2 [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	8,000	1,000
Level 2 [Member] | Loans Receivable [Member]
Financial assets:
Loans	0	0
Level 2 [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	0	0
Level 2 [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities	44,000	38,000
Level 2 [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Financial assets:
Derivative assets	1,000	1,000
Level 2 [Member] | Warrants [Member]
Financial assets:
Derivative assets	0	0
Level 3 [Member]
Financial assets:
Cash	0	0
Total financial assets	3,974,000	3,772,000
Financial liabilities:
Liabilities for net financial guarantees written	668,000	476,000
Long-term debt	15,000	14,000
Total financial liabilities	799,000	644,000
Level 3 [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	0	0
Level 3 [Member] | Loans Receivable [Member]
Financial assets:
Loans	2,000	10,000
Level 3 [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	0	0
Level 3 [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities	0	0
Level 3 [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Financial assets:
Derivative assets	30,000	26,000
Level 3 [Member] | Warrants [Member]
Financial assets:
Derivative assets	1,000	1,000
Commercial Mortgage Backed Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	15,000	15,000
Municipal Bonds [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	86,000	102,000
Corporate Debt Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	679,000	598,000
Debt Security, Government, Non-US [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	79,000	76,000
US Government Debt Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	63,000	65,000
Residential Mortgage-Backed Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	240,000	238,000
Collateralized Debt Obligations [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	137,000	137,000
Asset-backed Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	223,000	224,000
Fair Value, Recurring [Member]
Financial assets:
Total financial assets	7,045,000	6,715,000
Financial liabilities:
Liabilities for net financial guarantees written	668,000	476,000
Long-term debt	779,000	878,000
Total financial liabilities	5,717,000	5,586,000
Fair Value, Recurring [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	15,000	15,000
Fair Value, Recurring [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	367,000	507,000
Fair Value, Recurring [Member] | Loans Receivable [Member]
Financial assets:
Loans	2,000	10,000
Fair Value, Recurring [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	545,000	556,000
Fair Value, Recurring [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	223,000	224,000
Fair Value, Recurring [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	137,000	137,000
Fair Value, Recurring [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	240,000	238,000
Fair Value, Recurring [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	63,000	65,000
Fair Value, Recurring [Member] | Debt Security, Government, Non-US [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	79,000	76,000
Fair Value, Recurring [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	679,000	598,000
Fair Value, Recurring [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	86,000	102,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities	44,000	38,000
Fair Value, Recurring [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Financial assets:
Derivative assets	30,000	27,000
Fair Value, Recurring [Member] | Warrants [Member]
Financial assets:
Derivative assets	1,000	1,000
Fair Value, Recurring [Member] | Level 1 [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 1 [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 1 [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 1 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 1 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	63,000	65,000
Fair Value, Recurring [Member] | Level 1 [Member] | Debt Security, Government, Non-US [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	79,000	76,000
Fair Value, Recurring [Member] | Level 1 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 1 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 2 [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	15,000	15,000
Fair Value, Recurring [Member] | Level 2 [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	155,000	157,000
Fair Value, Recurring [Member] | Level 2 [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	137,000	137,000
Fair Value, Recurring [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	240,000	238,000
Fair Value, Recurring [Member] | Level 2 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 2 [Member] | Debt Security, Government, Non-US [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 2 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	667,000	585,000
Fair Value, Recurring [Member] | Level 2 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	86,000	102,000
Fair Value, Recurring [Member] | Level 3 [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 3 [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	69,000	67,000
Fair Value, Recurring [Member] | Level 3 [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 3 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 3 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 3 [Member] | Debt Security, Government, Non-US [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Fair Value, Recurring [Member] | Level 3 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	13,000	12,000
Fair Value, Recurring [Member] | Level 3 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Collateral Pledged [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	61,000	64,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Collateral Pledged [Member] | Short-term Investments [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	61,000	64,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	61,000	64,000
Collateral Pledged [Member] | Short-term Investments [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	61,000	64,000
Collateral Pledged [Member] | Fair Value, Recurring [Member] | Short-term Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	61,000	64,000
Collateral Pledged [Member] | Fair Value, Recurring [Member] | Level 1 [Member] | Short-term Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	61,000	64,000
Collateral Pledged [Member] | Fair Value, Recurring [Member] | Level 2 [Member] | Short-term Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Collateral Pledged [Member] | Fair Value, Recurring [Member] | Level 3 [Member] | Short-term Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Asset Pledged as Collateral [Member] | Fixed Income Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	61,000	64,000
Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	2,119,000	1,967,000
Financial assets:
Loans	1,856,000	1,829,000
Derivative assets	243,000	239,000
Long-term Debt	3,060,000	3,107,000
Financial liabilities:
Derivative liabilities	1,174,000	1,048,000
Long-term debt	2,869,000	2,788,000
Variable Interest Entity, Primary Beneficiary [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	2,003,000	1,828,000
Variable Interest Entity, Primary Beneficiary [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	100,000	96,000
Financial liabilities:
Debt Securities, Available-for-sale, Amortized Cost	99,000	99,000
Variable Interest Entity, Primary Beneficiary [Member] | US States and Political Subdivisions Debt Securities
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	16,000	43,000
Variable Interest Entity, Primary Beneficiary [Member] | Reported Value Measurement [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	256,000	17,000
Loans	1,856,000	1,829,000
Financial liabilities:
Long-term debt	3,060,000	3,107,000
Variable Interest Entity, Primary Beneficiary [Member] | Reported Value Measurement [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	2,003,000	1,828,000
Variable Interest Entity, Primary Beneficiary [Member] | Reported Value Measurement [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	100,000		$ 96,000
Variable Interest Entity, Primary Beneficiary [Member] | Reported Value Measurement [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	198,000	190,000
Financial liabilities:
Derivative liabilities	1,174,000	1,048,000
Variable Interest Entity, Primary Beneficiary [Member] | Reported Value Measurement [Member] | Currency Swaps [Member]
Financial assets:
Derivative assets	45,000	49,000
Variable Interest Entity, Primary Beneficiary [Member] | Reported Value Measurement [Member] | US States and Political Subdivisions Debt Securities
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Debt Securities, Trading	16,000	43,000
Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	256,000	17,000
Loans	0	0
Financial liabilities:
Long-term debt	0	0
Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed maturity securities, at fair value	0	0
Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	0	0
Financial liabilities:
Derivative liabilities	0	0
Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member] | Currency Swaps [Member]
Financial assets:
Derivative assets	0	0
Variable Interest Entity, Primary Beneficiary [Member] | Level 1 [Member] | US States and Political Subdivisions Debt Securities
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Debt Securities, Trading	0	0
Variable Interest Entity, Primary Beneficiary [Member] | Level 2 [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	0	0
Loans	0	0
Financial liabilities:
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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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