Fair Value (Fair Value Of Financial Instruments) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	$ 320,920,000	$ 159,956,000
Investment securities	1,184,399,000	1,209,701,000
Loans Held-for-sale, Fair Value Disclosure	23,901,000	12,278,000
Derivative Assets	1,000,000.0	221,000
Impaired Loan Fair Value	2,154,000	2,090,000
Other loans	6,451,435,000	6,426,869,000
Loans receivable, net	6,478,525,000	6,441,458,000
Time deposits	1,069,209,000	1,145,537,000
Other	2,667,000	1,273,000
Total deposits	1,071,876,000	1,146,810,000
Short-term borrowings	193,373,000	230,657,000
Long-term debt	150,782,000	200,726,000
Subordinated debentures/notes	13,635,000	14,372,000
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	1,186,000	575,000
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	1,035,000	221,000
Impaired Loan Fair Value		2,090,000
Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	4,617,000	1,870,000
Loans [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	4,617,000	1,870,000
Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,982,000	1,993,000
Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226,000	226,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	320,920,000	159,956,000
Derivative Assets	0	0
Other	2,667,000	1,273,000
Total deposits	2,667,000	1,273,000
Fair Value, Inputs, Level 1 [Member] | Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,519,000	1,537,000
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,184,399,000	1,209,701,000
Loans Held-for-sale, Fair Value Disclosure	23,901,000	12,278,000
Derivative Assets	1,035,000	221,000
Loans receivable, net	24,936,000	12,499,000
Time deposits	1,069,209,000	1,145,537,000
Total deposits	1,069,209,000	1,145,537,000
Short-term borrowings	193,373,000	230,657,000
Long-term debt	150,782,000	200,726,000
Subordinated debentures/notes	13,635,000	14,372,000
Fair Value, Inputs, Level 2 [Member] | Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	4,617,000	1,870,000
Swap	4,617,000	1,870,000
Fair Value, Inputs, Level 2 [Member] | Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	1,186,000	575,000
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	0	0
Impaired Loan Fair Value	2,154,000	2,090,000
Other loans	6,451,435,000	6,426,869,000
Loans receivable, net	6,453,589,000	6,428,959,000
Fair Value, Inputs, Level 3 [Member] | Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	463,000	456,000
Fair Value, Inputs, Level 3 [Member] | Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	$ 226,000	$ 226,000