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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Goodwill impairment				$ 0	$ 2,350,000
Amortization during the year			$ 1,134,000	1,250,000	1,257,000
Core Deposits [Member]
Finite Lived Intangible Assets [Line Items]
Amortization during the year			70,000	115,000	160,000
Other Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
Amortization during the year			1,100,000	$ 1,100,000	1,100,000
Banking Segment [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill impairment	$ 0				0
SDN Reporting Unit [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill impairment		$ 2,400,000	$ 0
Courier Capital [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill impairment					0
HNP Capital [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill impairment					$ 0

X

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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