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Fair Value Measurements - Summary of Carrying Amount and Fair Value of Ambac's Financial Assets and Liabilities (Detail) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	$ 3,611,947,000
Financial assets:
Short term investments	908,235,000	$ 430,331,000
Other investments	428,556,000	391,217,000
Derivative assets	76,789,000	59,768,000
Other assets	4,148,000	4,516,000
Long-term Debt	2,929,227,000	2,928,929,000
Financial liabilities:
Derivative liabilities	86,923,000	76,999,000
Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	3,128,995,000	2,737,286,000
Financial assets:
Loans	4,375,761,000	4,287,664,000
Derivative assets	59,228,000	66,302,000
Long-term Debt	5,737,263,000	5,268,596,000
Financial liabilities:
Derivative liabilities	1,781,903,000	1,712,062,000
Long-term debt	5,401,992,000	5,268,596,000
Short-term Investments [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	908,235,000	430,331,000
Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	2,858,404,000	2,737,286,000
Municipal Bonds [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	270,591,000	0
Total Fair Value [Member]
Financial assets:
Cash	21,840,000	82,494,000
Reported Value Measurement [Member]
Financial assets:
Cash	21,840,000	82,494,000
Loans	10,124,000	9,913,000
Other assets	4,148,000	4,516,000
Total financial assets	11,720,253,000	11,185,865,000
Financial liabilities:
Liabilities for net financial guarantees written	(839,056,000)	(718,388,000)
Long-term debt	3,320,562,000	3,304,737,000
Total financial liabilities	10,087,206,000	9,643,706,000
Reported Value Measurement [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	3,254,000	999,000
Loans	4,375,761,000	4,287,664,000
Financial liabilities:
Long-term debt	5,737,263,000	5,268,596,000
Reported Value Measurement [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	908,235,000	430,331,000
Reported Value Measurement [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	428,556,000	391,217,000
Reported Value Measurement [Member] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	2,858,404,000	2,737,286,000
Reported Value Measurement [Member] | Municipal Bonds [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	270,591,000
Reported Value Measurement [Member] | Future [Member]
Financial assets:
Derivative assets	3,182,000
Financial liabilities:
Derivative liabilities	0	3,379,000
Reported Value Measurement [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities - interest rate swaps - asset position	0
Derivative liabilities	85,457,000	71,861,000
Reported Value Measurement [Member] | Interest Rate Swap [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial liabilities:
Derivative liabilities	1,781,903,000	1,712,062,000
Reported Value Measurement [Member] | Other Credit Derivatives [Member]
Financial liabilities:
Derivative liabilities	1,077,000	1,459,000
Other Assets [Member] | Reported Value Measurement [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	73,218,000	59,468,000
Interest Rate Swaps - Liability Position [Member] | Reported Value Measurement [Member] | Currency Swaps [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Derivative assets	59,228,000	66,302,000
Level 1 [Member]
Financial assets:
Cash	15,891,000	52,661,000
Total financial assets	1,203,358,000	553,964,000
Financial liabilities:
Liabilities for net financial guarantees written	0	0
Long-term debt	0	0
Total financial liabilities	0	3,379,000
Level 1 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	3,254,000	999,000
Loans	0	0
Financial liabilities:
Long-term debt	0	0
Level 1 [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	864,065,000	304,880,000
Level 1 [Member] | Equity Method Investments [Member]
Financial assets:
Other assets	0	0
Level 1 [Member] | Loans Receivable [Member]
Financial assets:
Loans	0	0
Level 1 [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	102,257,000	71,108,000
Level 1 [Member] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Level 1 [Member] | Municipal Bonds [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0
Level 1 [Member] | Future [Member]
Financial assets:
Derivative assets	3,182,000
Financial liabilities:
Derivative liabilities	0	3,379,000
Level 1 [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities - interest rate swaps - asset position	0
Derivative liabilities	0	0
Level 1 [Member] | Interest Rate Swap [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial liabilities:
Derivative liabilities	0	0
Level 1 [Member] | Other Credit Derivatives [Member]
Financial liabilities:
Derivative liabilities	0	0
Level 1 [Member] | Other Assets [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	0	0
Level 1 [Member] | Interest Rate Swaps - Liability Position [Member] | Currency Swaps [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Derivative assets	0	0
Level 2 [Member]
Financial assets:
Cash	5,949,000	29,833,000
Total financial assets	2,816,193,000	3,152,882,000
Financial liabilities:
Liabilities for net financial guarantees written	0	0
Long-term debt	2,942,229,000	2,909,272,000
Total financial liabilities	10,370,724,000	9,744,699,000
Level 2 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	0	0
Loans	0	0
Financial liabilities:
Long-term debt	5,561,135,000	5,051,504,000
Level 2 [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	44,170,000	125,451,000
Level 2 [Member] | Equity Method Investments [Member]
Financial assets:
Other assets	0	0
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] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Level 2 [Member] | Municipal Bonds [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	270,591,000
Level 2 [Member] | Future [Member]
Financial assets:
Derivative assets	0
Financial liabilities:
Derivative liabilities	0	0
Level 2 [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities - interest rate swaps - asset position
Derivative liabilities	85,457,000	71,861,000
Level 2 [Member] | Interest Rate Swap [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial liabilities:
Derivative liabilities	1,781,903,000	1,712,062,000
Level 2 [Member] | Other Credit Derivatives [Member]
Financial liabilities:
Derivative liabilities	0	0
Level 2 [Member] | Other Assets [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	19,107,000	12,008,000
Level 2 [Member] | Interest Rate Swaps - Liability Position [Member] | Currency Swaps [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Derivative assets	59,228,000	66,302,000
Level 3 [Member]
Financial assets:
Cash	0	0
Total financial assets	7,394,196,000	7,176,883,000
Financial liabilities:
Liabilities for net financial guarantees written	509,830,000	558,824,000
Long-term debt	382,084,000	350,694,000
Total financial liabilities	1,117,438,000	1,128,069,000
Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	0	0
Loans	4,375,761,000	4,287,664,000
Financial liabilities:
Long-term debt	224,447,000	217,092,000
Level 3 [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	0	0
Level 3 [Member] | Equity Method Investments [Member]
Financial assets:
Other assets	4,148,000	4,516,000
Level 3 [Member] | Loans Receivable [Member]
Financial assets:
Loans	12,187,000	11,620,000
Level 3 [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	17,730,000	16,266,000
Level 3 [Member] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	2,858,404,000	2,737,286,000
Level 3 [Member] | Municipal Bonds [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0
Level 3 [Member] | Future [Member]
Financial assets:
Derivative assets	0
Financial liabilities:
Derivative liabilities
Level 3 [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities - interest rate swaps - asset position	0
Derivative liabilities	0	0
Level 3 [Member] | Interest Rate Swap [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial liabilities:
Derivative liabilities	0	0
Level 3 [Member] | Other Credit Derivatives [Member]
Financial liabilities:
Derivative liabilities	1,077,000	1,459,000
Level 3 [Member] | Other Assets [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	54,111,000	47,460,000
Level 3 [Member] | Interest Rate Swaps - Liability Position [Member] | Currency Swaps [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Derivative assets	0	0
Municipal Bonds [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	424,884,000	879,919,000
Corporate Debt Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	1,233,544,000	1,278,122,000
Debt Security, Government, Non-US [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	31,292,000	30,834,000
US Government Debt Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	100,429,000	94,394,000
Residential Mortgage-Backed Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	256,285,000	258,607,000
Collateralized Debt Obligations [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	132,977,000	131,356,000
Asset-backed Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	440,400,000	442,443,000
Fair Value, Measurements, Recurring [Member]
Financial assets:
Total financial assets	11,698,535,000	11,163,670,000
Financial liabilities:
Liabilities for net financial guarantees written	509,830,000	558,824,000
Long-term debt	3,324,313,000	3,259,966,000
Total financial liabilities	11,488,162,000	10,876,147,000
Fair Value, Measurements, Recurring [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Restricted Cash and Cash Equivalents, Current	3,254,000	999,000
Loans	4,375,761,000	4,287,664,000
Financial liabilities:
Long-term debt	5,785,582,000	5,268,596,000
Fair Value, Measurements, Recurring [Member] | Short-term Investments [Member]
Financial assets:
Short term investments	908,235,000	430,331,000
Fair Value, Measurements, Recurring [Member] | Equity Method Investments [Member]
Financial assets:
Other assets	4,148,000	4,516,000
Fair Value, Measurements, Recurring [Member] | Loans Receivable [Member]
Financial assets:
Loans	12,187,000	11,620,000
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member]
Financial assets:
Other investments	404,775,000	367,315,000
Fair Value, Measurements, Recurring [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	440,400,000	442,443,000
Fair Value, Measurements, Recurring [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	132,977,000	131,356,000
Fair Value, Measurements, Recurring [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	256,285,000	258,607,000
Fair Value, Measurements, Recurring [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	100,429,000	94,394,000
Fair Value, Measurements, Recurring [Member] | Debt Security, Government, Non-US [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	31,292,000	30,834,000
Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	1,233,544,000	1,278,122,000
Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	2,858,404,000	2,737,286,000
Fair Value, Measurements, Recurring [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	424,884,000	879,919,000
Fair Value, Measurements, Recurring [Member] | Municipal Bonds [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	270,591,000
Fair Value, Measurements, Recurring [Member] | Future [Member]
Financial assets:
Derivative assets	3,182,000
Financial liabilities:
Derivative liabilities	0	3,379,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member]
Financial liabilities:
Derivative liabilities - interest rate swaps - asset position	0
Derivative liabilities	85,457,000	71,861,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial liabilities:
Derivative liabilities	1,781,903,000	1,712,062,000
Fair Value, Measurements, Recurring [Member] | Other Credit Derivatives [Member]
Financial liabilities:
Derivative liabilities	1,077,000	1,459,000
Fair Value, Measurements, Recurring [Member] | Other Assets [Member] | Interest Rate Swap [Member]
Financial assets:
Derivative assets	73,218,000	59,468,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Swaps - Liability Position [Member] | Currency Swaps [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial assets:
Derivative assets	59,228,000	66,302,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	100,429,000	94,394,000
Fair Value, Measurements, 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 income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	30,379,000	29,922,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	368,545,000	370,372,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	132,977,000	131,356,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	256,285,000	258,607,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, 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 income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	913,000	912,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	1,233,544,000	1,278,122,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	424,884,000	879,919,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Asset-backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	71,855,000	72,071,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Collateralized Debt Obligations [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Residential Mortgage-Backed Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, 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 income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Corporate Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Municipal Bonds [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0	$ 0
Collateral Pledged [Member] | US Government Debt Securities [Member] | Reported Value Measurement [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	83,901,000
Collateral Pledged [Member] | Fair Value, Measurements, Recurring [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	83,901,000
Collateral Pledged [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	83,901,000
Collateral Pledged [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	0
Collateral Pledged [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | US Government Debt Securities [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Fixed income securities, at fair value (amortized cost of $2,480,532 and $3,020,744)	$ 0

X

- Definition

Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]

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No definition available.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value portion of investments accounted under the equity method.

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Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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Amount of investments classified as other.

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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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