Securities - Unrealized Losses (Details) $ in Thousands	Sep. 30, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Less than 12 Months
Fair Value	$ 18,633	$ 78,881
Unrealized Losses	$ 229	$ 339
Number of Securities \| security	21	21
12 Months or More
Fair Value	$ 26	$ 29,185
Unrealized Losses	$ 0	$ 247
Number of Securities \| security	1	15
Total
Fair Value	$ 18,659	$ 108,066
Unrealized Losses	$ 229	$ 586
Number of Securities \| security	22	36
Mortgage-backed - GSE residential
Less than 12 Months
Fair Value	$ 0	$ 7,959
Unrealized Losses	$ 0	$ 38
Number of Securities \| security	0	2
12 Months or More
Fair Value	$ 0	$ 20,396
Unrealized Losses	$ 0	$ 155
Number of Securities \| security	0	4
Total
Fair Value	$ 0	$ 28,355
Unrealized Losses	$ 0	$ 193
Number of Securities \| security	0	6
Collateralized mortgage obligations - GSE residential
Less than 12 Months
Fair Value	$ 3,178	$ 48,980
Unrealized Losses	$ 7	$ 199
Number of Securities \| security	1	7
12 Months or More
Fair Value	$ 0	$ 8,622
Unrealized Losses	$ 0	$ 90
Number of Securities \| security	0	9
Total
Fair Value	$ 3,178	$ 57,602
Unrealized Losses	$ 7	$ 289
Number of Securities \| security	1	16
State and political subdivisions
Less than 12 Months
Fair Value	$ 14,998	$ 21,412
Unrealized Losses	$ 220	$ 102
Number of Securities \| security	19	11
12 Months or More
Fair Value	$ 26	$ 167
Unrealized Losses	$ 0	$ 2
Number of Securities \| security	1	2
Total
Fair Value	$ 15,024	$ 21,579
Unrealized Losses	$ 220	$ 104
Number of Securities \| security	20	13
Corporate bonds
Less than 12 Months
Fair Value	$ 457	$ 530
Unrealized Losses	$ 2	$ 0
Number of Securities \| security	1	1
12 Months or More
Fair Value	$ 0	$ 0
Unrealized Losses	$ 0	$ 0
Number of Securities \| security	0	0
Total
Fair Value	$ 457	$ 530
Unrealized Losses	$ 2	$ 0
Number of Securities \| security	1	1

Available For Sale Securities, Less Than Twelve Months [Abstract]

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Available For Sale Securities, Twelve Months Or Longer [Abstract]

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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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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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