Summary of Significant Accounting Policies - Schedule of Changes in the Balance of Each Component of Accumulated Other Comprehensive Earnings (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Changes in the balance of each component of accumulated other comprehensive earnings (loss)
Beginning balance			$ 49,826				$ 49,826
Net current-period other comprehensive earnings (loss)	$ (81,248)	$ (97,563)	(115,581)	$ (12,240)	$ 15,177	$ (44,747)	(294,392)	$ (41,810)
Ending balance	(244,566)						(244,566)
Unrealized Gains and Losses on Available-for-Sale Securities
Changes in the balance of each component of accumulated other comprehensive earnings (loss)
Beginning balance	(163,318)		$ 49,826	79,144		$ 108,714	49,826	108,714
Other comprehensive earnings (loss) before reclassifications	(82,785)			(12,114)			(296,422)	(40,307)
Amounts reclassified from accumulated other comprehensive earnings	1,537			(126)			2,030	(1,503)
Net current-period other comprehensive earnings (loss)	(81,248)			(12,240)			(294,392)	(41,810)
Ending balance	(244,566)	$ (163,318)		66,904	$ 79,144		(244,566)	66,904
Balance of securities for which an allowance for credit losses has not been recognized in net earnings	$ 1,520			$ 426			$ 1,520	$ 426

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) without allowance for credit loss.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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