Fair Value Measurements (Fair Value Measurement and Assumptions) (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Doubtful and Impaired commercial collateral dependent loans	$ 29,899,000	$ 29,899,000	$ 51,326,000
Impaired commercial collateral dependent receivables appraisals to determine fair value within immediately preceding twelve months	0	0	0
Impaired collateral dependent commercial loans with internal evaluation completed within last twelve months	29,899,000	29,899,000	51,326,000
Charges to allowance for probable loan losses in connection with other real estate owned	0	0	2,000
Adjustment to fair value in connection with other real estate owned	2,213,000	2,510,000	1,627,000
Fair Value, Measurements, Nonrecurring
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Change in net provision, impaired loans	5,581,000	5,581,000	2,346,000
Change in net provision, other real estate owned	2,510,000	2,510,000	1,627,000
Fair Value, Measurements, Nonrecurring | Estimated Fair Value
Assets:
Watch-List doubtful loans	29,763,000	29,763,000	30,743,000
Non-financial assets:
Other real estate owned	546,000	546,000	5,653,000
Fair Value, Measurements, Nonrecurring | Estimated Fair Value | Fair Value, Inputs, Level 3
Assets:
Watch-List doubtful loans	29,763,000	29,763,000	30,743,000
Non-financial assets:
Other real estate owned	$ 546,000	$ 546,000	$ 5,653,000