Loans (Non-accrual Loans, Loans Past Due 90 Days And Other Real Estate Owned And Delinquent Loans By Loan Category) (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	$ 12,275,000	$ 5,796,000
Loans past due 90 days or more and still accruing	24,000	3,264,000
Total non-performing loans	2,482,452,000	1,814,488,000
Other real estate owned	0	0
Total non-performing assets	12,299,000	9,060,000
Non-Accrual Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	12,275,000	5,796,000
Non-Performing Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-performing loans	12,299,000	9,060,000
SBL Non Real Estate [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	2,935,000	3,693,000
Total non-performing loans	293,488,000	84,579,000
SBL Non Real Estate [Member] | Non-Accrual Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	2,935,000	3,693,000
SBL Commercial Mortgage [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	7,517,000	1,047,000
Total non-performing loans	270,264,000	218,110,000
SBL Commercial Mortgage [Member] | Non-Accrual Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	7,517,000	1,047,000
SBL Construction [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	711,000	711,000
Total non-performing loans	27,169,000	45,310,000
SBL Construction [Member] | Non-Accrual Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	711,000	711,000
Direct Lease Financing [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	804,000
Total non-performing loans	430,675,000	434,460,000
Direct Lease Financing [Member] | Non-Accrual Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	804,000
Consumer Loan [Member] | Non-Accrual Loans [Member]
Financing Receivables Past Due and Other Real Estate Owned [Line Items]
Total non-accrual loans	$ 308,000	$ 345,000