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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Fair Value of Financial Instruments - Quantitative Information About Level 3 Fair Value Measurements (Details)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 1,686,502,000	$ 1,551,336,000
Asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	3,831,000	4,253,000
Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	1,686,503,000	1,551,339,000
Recurring \| Asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	3,831,000	4,253,000
Recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	10,584,000	6,476,000
Recurring \| Level 3 \| Corporate bonds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 4,892,000
Recurring \| Level 3 \| Corporate bonds \| Third Party Valuation \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	90
Recurring \| Level 3 \| Corporate bonds \| Third Party Valuation \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	100
Recurring \| Level 3 \| Asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 869,000	$ 801,000
Recurring \| Level 3 \| Asset-backed securities \| Discounted cash flow \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	0.04
Recurring \| Level 3 \| Asset-backed securities \| Discounted cash flow \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	0.06
Recurring \| Level 3 \| Fixed Maturities Federal Home Loan Mortgage Corporation
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 4,823,000
Recurring \| Level 3 \| Fixed Maturities Federal Home Loan Mortgage Corporation \| Third Party Valuation \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	45
Recurring \| Level 3 \| Fixed Maturities Federal Home Loan Mortgage Corporation \| Third Party Valuation \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	55