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Investment Securities - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Securities transferred from available-for-sale to held-to-maturity	$ 0	$ 0	$ 27,422,000
Unrealized pre-tax loss from transfer of available-for-sale securities to held-to-maturity			278,000
Amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity	$ 524,000	$ 445,000	$ 516,000

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Amortization Of Net Unrealized Loss On Available-For-Sale Securities Transferred To Held-To-Maturity

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Available-for-sale Securities, Transferred to Held-to-maturity Securities

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Available-for-sale Securities, Transferred to Held-to-maturity Securities, Unrealized Gain (Loss)

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