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
Mar. 31, 2021	Mar. 31, 2020
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance	$ 108,714
Accounting Standards Update [Extensible List]		ASU 2016-13
Net current-period other comprehensive loss	(44,747)	$ (13,031)
Ending balance	63,967
Balance of securities for which an allowance for credit losses has been recognized in net earnings	463	5,727
Unrealized Gains and Losses on Available-for-Sale Securities
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance	108,714	52,473
Other comprehensive loss before reclassifications	(43,795)	(11,880)
Amounts reclassified from accumulated other comprehensive earnings	(952)	(1,151)
Ending balance	63,967	39,464
Unrealized Gains and Losses on Available-for-Sale Securities \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance		$ 22
Accounting Standards Update [Extensible List]		ASU 2016-13
Unrealized Gains and Losses on Available-for-Sale Securities \| Cumulative Effect, Period of Adoption, Adjusted Balance
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance	$ 108,714	$ 52,495

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

No definition available.

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- Definition

Indicates amendment to accounting standards.

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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) with 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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