Investment Securities Debt Securities, Available-for-Sale - Continuous Loss Position (Details) $ in Thousands	Dec. 31, 2020 USD ($) investment	Dec. 31, 2019 USD ($) investment
Debt Securities, Available-for-sale [Line Items]
Debt securities, temporarily impaired, less than 12 months, fair value	$ 53,393	$ 53,290
Debt Securities, temporarily impaired, less than 12 months, unrealized loss	287	397
Debt securities, temporarily impaired, 12 months or longer, fair value	2,107	5,060
Debt securities, temporarily impaired, 12 months or longer, unrealized loss	3	70
Debt securities, temporarily impaired, fair value	55,500	58,350
Debt securities, temporarily impaired, unrealized loss	$ 290	$ 467
Number of debt securities in loss positions \| investment	14	26
Residential federal agency MBS
Debt Securities, Available-for-sale [Line Items]
Debt securities, temporarily impaired, less than 12 months, fair value	$ 51,396	$ 36,464
Debt Securities, temporarily impaired, less than 12 months, unrealized loss	284	263
Debt securities, temporarily impaired, 12 months or longer, fair value	2,107	5,060
Debt securities, temporarily impaired, 12 months or longer, unrealized loss	3	70
Debt securities, temporarily impaired, fair value	53,503	41,524
Debt securities, temporarily impaired, unrealized loss	$ 287	$ 333
Number of debt securities in loss positions \| investment	10	11
Taxable municipal securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, temporarily impaired, less than 12 months, fair value	$ 1,997	$ 16,826
Debt Securities, temporarily impaired, less than 12 months, unrealized loss	3	134
Debt securities, temporarily impaired, 12 months or longer, fair value	0	0
Debt securities, temporarily impaired, 12 months or longer, unrealized loss	0	0
Debt securities, temporarily impaired, fair value	1,997	16,826
Debt securities, temporarily impaired, unrealized loss	$ 3	$ 134
Number of debt securities in loss positions \| investment	4	15

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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