Other Comprehensive (Loss) Income - Reclassification adjustments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Securities available for sale and transferred securities: Before Tax Amount
Change in net unrealized gain/loss during the period	$ (19,112)	$ 9,458
Reclassification adjustment for net gains included in net income	(516)
Total other comprehensive loss	(19,628)	9,458
Securities available for sale and transferred securities: Tax (Expense) Benefit
Change in net unrealized gain/loss during the period	4,014	(1,985)
Reclassification adjustment for net gains included in net income	108
Total other comprehensive loss	4,122	(1,985)
Securities available for sale and transferred securities:
Change in net unrealized gain/loss during the period	(15,098)	7,473
Reclassification adjustment for net gains included in net income	(408)
Total other comprehensive income (loss)	$ (15,506)	$ 7,473

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

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