Other Comprehensive Income (Loss) - Summary of Transfer of AFS Securities to HTM (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Reclassification of Available-for-Sale Securities to Held-to-maturity Roll Forward [Roll Forward]
Balance at beginning of period	$ 223,726	$ 212,508
Balance at end of period	228,184	215,257
Accumulated Net Gain (Loss) on Securities Transferred from Available-for-Sale to Held-to-Maturity
Reclassification of Available-for-Sale Securities to Held-to-maturity Roll Forward [Roll Forward]
Balance at beginning of period	(133)	(182)
Reclassification of net realized gains during the period	11	10
Related deferred taxes	(2)	(2)
Net change	9	8
Balance at end of period	$ (124)	$ (174)

Reclassification of Available-for-Sale Securities to Held-to-maturity Roll Forward [Roll Forward]

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

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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