Fair Value (Fair Value Of Financial Instruments) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	$ 877,395,000	$ 370,474,000
Investment securities	1,553,218,000	1,059,341,000
Loans Held-for-sale, Fair Value Disclosure	8,944,000	31,666,000
Derivative Assets	400,000	1,500,000
Impaired Loan Fair Value	848,000	6,924,000
Other loans	6,834,592,000	7,072,339,000
Loans receivable, net	6,844,788,000	7,112,474,000
Time deposits	749,710,000	870,804,000
Other	5,389,000	1,379,000
Total deposits	755,099,000	872,183,000
Short-term borrowings	235,979,000	342,230,000
Long-term debt		31,376,000
Subordinated debentures/notes	197,119,000	179,147,000
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	436,000	885,000
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	404,000	1,545,000
Impaired Loan Fair Value		6,924,000
Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	2,258,000	3,934,000
Loans [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	2,258,000	3,934,000
Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	2,070,000	2,511,000
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	877,395,000	370,474,000
Investment securities	387,682,000
Derivative Assets	0	0
Other	5,389,000	1,379,000
Total deposits	5,389,000	1,379,000
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	1,579,000	2,026,000
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,165,536,000	1,059,341,000
Loans Held-for-sale, Fair Value Disclosure	8,944,000	31,666,000
Derivative Assets	404,000	1,545,000
Loans receivable, net	9,348,000	33,211,000
Time deposits	749,710,000	870,804,000
Total deposits	749,710,000	870,804,000
Short-term borrowings	235,979,000	342,230,000
Long-term debt		31,376,000
Subordinated debentures/notes	197,119,000	179,147,000
Fair Value, Inputs, Level 2 [Member] | Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	2,258,000	3,934,000
Swap	2,258,000	3,934,000
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	436,000	885,000
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	0	0
Impaired Loan Fair Value	848,000	6,924,000
Other loans	6,834,592,000	7,072,339,000
Loans receivable, net	6,835,440,000	7,079,263,000
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	491,000	485,000
Fair Value, Inputs, Level 3 [Member] | Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	$ 226,000	$ 226,000