Other Comprehensive Income - Changes in accumulated other comprehensive income (loss), net of tax (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Securities, Available-for-sale [Abstract]
Beginning balance	$ 4,804	$ 15,942	$ 16,168	$ 3,109
Other comprehensive income (loss) before reclassifications	(5,703)	(624)	(16,666)	13,354
Amounts reclassified from accumulated other comprehensive income (loss)	(1,133)	(86)	(1,534)	(1,231)
Net other comprehensive income (loss) during the period	(6,836)	(710)	(18,200)	12,123
Ending balance	(2,032)	15,232	(2,032)	15,232
Derivatives
Beginning balance	(284)	(1,274)	(668)	(150)
Other comprehensive income (loss) before reclassifications	0	24	769	(1,324)
Amounts reclassified from accumulated other comprehensive income (loss)	0	289	(385)	513
Total unrealized gain (loss)	0	313	384	(811)
Ending balance	(284)	(961)	(284)	(961)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Beginning balance	4,520	14,668	15,500	2,959
Other comprehensive income (loss) before reclassifications	(5,703)	(600)	(15,897)	12,030
Amounts reclassified from accumulated other comprehensive income (loss)	(1,133)	203	(1,919)	(718)
Other comprehensive income (loss)	(6,836)	(397)	(17,816)	11,312
Ending balance	$ (2,316)	$ 14,271	$ (2,316)	$ 14,271

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The amount of oci before reclassification net of tax attributable to parent.

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The amount of other comprehensive income loss net of tax portion attributable to parent.

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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).

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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, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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