Fair Value of Financial Instruments - Quantitative Information About Level 3 Fair Value Measurements (Details) $ in Thousands	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total Available-for-Sale Fixed Maturities	$ 1,589,248	$ 1,686,502
Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total Available-for-Sale Fixed Maturities	1,589,248	1,686,503
Recurring \| Fixed Maturities asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total Available-for-Sale Fixed Maturities	3,061	3,831
Recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total Available-for-Sale Fixed Maturities	276	10,584
Recurring \| Level 3 \| Fixed Maturities asset-backed securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total Available-for-Sale Fixed Maturities	$ 276	$ 869
Recurring \| Level 3 \| Fixed Maturities asset-backed securities \| Book Value \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	0
Recurring \| Level 3 \| Fixed Maturities asset-backed securities \| Book Value \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities, range of weighted average significant unobservable inputs	1

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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