Investments - Summarized Fair Value and Gross Unrealized Losses on Securities Available for Sale (Details) $ in Thousands	Mar. 31, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Number of issues \| security	61	107
Less than 12 months, Fair value	$ 61,159	$ 82,130
Less than 12 months, Unrealized losses	$ (1,564)	$ (6,045)
12 months or longer, Number of issues \| security	440	401
12 months or longer, Fair value	$ 564,993	$ 560,745
12 months or longer, Unrealized losses	$ (76,412)	$ (85,470)
Fixed Maturities \| U.S. government obligations and agencies
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Number of issues \| security	2	2
Less than 12 months, Fair value	$ 523	$ 2,721
Less than 12 months, Unrealized losses	$ (1)	$ (110)
12 months or longer, Number of issues \| security	6	5
12 months or longer, Fair value	$ 11,816	$ 8,943
12 months or longer, Unrealized losses	$ (762)	$ (828)
Fixed Maturities \| Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Number of issues \| security	22	40
Less than 12 months, Fair value	$ 20,332	$ 26,563
Less than 12 months, Unrealized losses	$ (421)	$ (2,910)
12 months or longer, Number of issues \| security	258	247
12 months or longer, Fair value	$ 319,002	$ 325,992
12 months or longer, Unrealized losses	$ (39,830)	$ (46,451)
Fixed Maturities \| Mortgage-backed and asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Number of issues \| security	36	64
Less than 12 months, Fair value	$ 39,815	$ 52,751
Less than 12 months, Unrealized losses	$ (1,073)	$ (2,974)
12 months or longer, Number of issues \| security	172	146
12 months or longer, Fair value	$ 227,174	$ 219,189
12 months or longer, Unrealized losses	$ (34,596)	$ (36,733)
Fixed Maturities \| Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Number of issues \| security	0	0
Less than 12 months, Fair value	$ 0	$ 0
Less than 12 months, Unrealized losses	$ 0	$ 0
12 months or longer, Number of issues \| security	3	3
12 months or longer, Fair value	$ 6,900	$ 6,621
12 months or longer, Unrealized losses	$ (1,179)	$ (1,458)
Fixed Maturities \| Redeemable preferred stock
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Number of issues \| security	1	1
Less than 12 months, Fair value	$ 489	$ 95
Less than 12 months, Unrealized losses	$ (69)	$ (51)
12 months or longer, Number of issues \| security	1	0
12 months or longer, Fair value	$ 101	$ 0
12 months or longer, Unrealized losses	$ (45)	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Name Accounting Standards Codification
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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