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Securities - Unrealized Loss Positions (Details)	Dec. 31, 2019 USD ($) security	Dec. 31, 2018 USD ($)
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position	19	16
Greater than 12 months in an unrealized loss position	15	61
Total	34	77
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 2,602,000	$ 1,256,000
Greater than 12 months in an unrealized loss position	1,181,000	7,592,000
Total	3,783,000	8,848,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	129,582,000	86,856,000
Greater than 12 months in an unrealized loss position	45,240,000	197,238,000
Total	$ 174,822,000	$ 284,094,000
US Treasury Securities [Member]
Securities Available-for-Sale, Number of Securities
Greater than 12 months in an unrealized loss position		1
Total		1
Securities Available-for-Sale, Unrealized Losses
Greater than 12 months in an unrealized loss position		$ 83,000
Total		83,000
Securities Available-for-Sale, Fair Value
Greater than 12 months in an unrealized loss position		3,923,000
Total		$ 3,923,000
US Government Corporations and Agencies Securities [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position		3
Greater than 12 months in an unrealized loss position	4	1
Total	4	4
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position		$ 100,000
Greater than 12 months in an unrealized loss position	$ 165,000	61,000
Total	165,000	161,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position		7,385,000
Greater than 12 months in an unrealized loss position	8,337,000	3,566,000
Total	$ 8,337,000	$ 10,951,000
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	2	11
Total	5	11
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	$ 377,000
Total	19,000	377,000
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	11,439,000
Total	$ 3,861,000	$ 11,439,000
US States and Political Subdivisions Debt Securities [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position	6	4
Greater than 12 months in an unrealized loss position	2	33
Total	8	37
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 1,665,000	$ 126,000
Greater than 12 months in an unrealized loss position	766,000	4,835,000
Total	2,431,000	4,961,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	41,043,000	17,713,000
Greater than 12 months in an unrealized loss position	6,593,000	110,326,000
Total	$ 47,636,000	$ 128,039,000
Collateralized Mortgage Obligations [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position	2	2
Greater than 12 months in an unrealized loss position	2	10
Total	4	12
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 26,000	$ 309,000
Greater than 12 months in an unrealized loss position	12,000	1,835,000
Total	38,000	2,144,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	9,054,000	15,211,000
Greater than 12 months in an unrealized loss position	1,209,000	43,687,000
Total	$ 10,263,000	$ 58,898,000
Asset-backed Securities [Member]
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position | security	4
Greater than 12 months in an unrealized loss position	1	4
Total	5	4
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 839,000
Greater than 12 months in an unrealized loss position	48,000	$ 225,000
Total	887,000	225,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	54,540,000
Greater than 12 months in an unrealized loss position	3,238,000	16,473,000
Total	$ 57,778,000	$ 16,473,000
Collateralized loan obligations
Securities Available-for-Sale, Number of Securities
Less than 12 months in an unrealized loss position	4	7
Greater than 12 months in an unrealized loss position	4	1
Total	8	8
Securities Available-for-Sale, Unrealized Losses
Less than 12 months in an unrealized loss position	$ 62,000	$ 721,000
Greater than 12 months in an unrealized loss position	181,000	176,000
Total	243,000	897,000
Securities Available-for-Sale, Fair Value
Less than 12 months in an unrealized loss position	21,927,000	46,547,000
Greater than 12 months in an unrealized loss position	25,020,000	7,824,000
Total	$ 46,947,000	$ 54,371,000

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