Other Comprehensive (Loss) Income - Activity in AOCI, net of tax (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract]
Securities Available For Sale, Beginning balance	$ 15,083	$ 4,839
Securities Available For Sale, Other comprehensive income/(loss) before reclassifications	(15,098)	7,473
Securities Available For Sale, Amounts reclassified from accumulated other comprehensive income	(408)
Securities Available For Sale, Net other comprehensive income/(loss) during period	(15,506)	7,473
Securities Available For Sale, Ending balance	(423)	12,312
Post-retirement Benefit, Beginning balance	(79)	(244)
Post-retirement Benefit, Ending balance	(79)	(244)
Accumulated Other Comprehensive Income (Loss), Beginning balance	15,004	4,595
Accumulated Other Comprehensive Income (Loss), Other comprehensive income/(loss) before reclassifications	(15,098)	7,473
Accumulated Other Comprehensive Income (Loss), Amounts reclassified from accumulated other comprehensive income	(408)	0
Accumulated Other Comprehensive Income (loss), Net other comprehensive income/(loss) during period	(15,506)	7,473
Accumulated Other Comprehensive Income (Loss), Ending balance	$ (502)	$ 12,068

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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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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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).

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

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