Investments - Cost or Amortized Cost and Fair Value of Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,150,524	$ 1,061,192
Allowance for Expected Credit Losses	(724)	(489)	$ (186)
Gross Unrealized Gains	105	1,129
Gross Unrealized Losses	(153,122)	(21,377)
Fair Value	996,783	1,040,455
U.S. government obligations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	12,602	27,076
Allowance for Expected Credit Losses	0	0
Gross Unrealized Gains	0	64
Gross Unrealized Losses	(1,004)	(334)
Fair Value	11,598	26,806
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	781,131	687,058
Allowance for Expected Credit Losses	(589)	(371)
Gross Unrealized Gains	42	843
Gross Unrealized Losses	(105,221)	(13,725)
Fair Value	675,363	673,805
Mortgage-backed and asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	332,444	322,844
Allowance for Expected Credit Losses	0	0
Gross Unrealized Gains	63	194
Gross Unrealized Losses	(42,774)	(6,920)
Fair Value	289,733	316,118
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	14,924	14,925
Allowance for Expected Credit Losses	0	(1)
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2,486)	(350)
Fair Value	12,438	14,574
Redeemable preferred stock
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,423	9,289
Allowance for Expected Credit Losses	(135)	(117)	$ (38)
Gross Unrealized Gains	0	28
Gross Unrealized Losses	(1,637)	(48)
Fair Value	$ 7,651	$ 9,152

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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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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Amount of allowance for credit loss on 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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