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Securities - Unrealized Loss Positions (Details)	Mar. 31, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	28	19
Greater than 12 months in an unrealized loss position | security	12	15
Total	40	34
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 7,306,000	$ 2,602,000
Greater than 12 months in an unrealized loss position	4,260,000	1,181,000
Total	11,566,000	3,783,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	113,063,000	129,582,000
Greater than 12 months in an unrealized loss position	55,109,000	45,240,000
Total	$ 168,172,000	$ 174,822,000
US Government Corporations and Agencies Securities [Member]
Securities Available-for-Sale, Number of Securities
Greater than 12 months in an unrealized loss position | security	4	4
Total	4	4
Securities Available-for-Sale, Unrealized Losses
Greater than 12 months in an unrealized loss position	$ 147,000	$ 165,000
Total	147,000	165,000
Securities Available-for-Sale, Fair Value
Greater than 12 months in an unrealized loss position	7,723,000	8,337,000
Total	$ 7,723,000	$ 8,337,000
Mortgage Backed Securities, Issued by US Government Agencies [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security		3
Greater than 12 months in an unrealized loss position | security		2
Total		5
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position		$ 10,000
Greater than 12 months in an unrealized loss position		9,000
Total		19,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position		3,018,000
Greater than 12 months in an unrealized loss position		843,000
Total		$ 3,861,000
US States and Political Subdivisions Debt Securities [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	4	6
Greater than 12 months in an unrealized loss position | security	2	2
Total	6	8
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 588,000	$ 1,665,000
Greater than 12 months in an unrealized loss position	1,099,000	766,000
Total	1,687,000	2,431,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	25,038,000	41,043,000
Greater than 12 months in an unrealized loss position	5,904,000	6,593,000
Total	$ 30,942,000	$ 47,636,000
Collateralized Mortgage Obligations [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	12	2
Greater than 12 months in an unrealized loss position | security	2	2
Total	14	4
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 3,339,000	$ 26,000
Greater than 12 months in an unrealized loss position	71,000	12,000
Total	3,410,000	38,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	35,811,000	9,054,000
Greater than 12 months in an unrealized loss position	1,051,000	1,209,000
Total	$ 36,862,000	$ 10,263,000
Asset-backed Securities [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	9	4
Greater than 12 months in an unrealized loss position | security	2	1
Total	11	5
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 2,530,000	$ 839,000
Greater than 12 months in an unrealized loss position	1,958,000	48,000
Total	4,488,000	887,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	36,074,000	54,540,000
Greater than 12 months in an unrealized loss position	29,244,000	3,238,000
Total	$ 65,318,000	$ 57,778,000
Collateralized loan obligations
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	3	4
Greater than 12 months in an unrealized loss position | security	2	4
Total	5	8
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 849,000	$ 62,000
Greater than 12 months in an unrealized loss position	985,000	181,000
Total	1,834,000	243,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	16,140,000	21,927,000
Greater than 12 months in an unrealized loss position	11,187,000	25,020,000
Total	$ 27,327,000	$ 46,947,000

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