Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	$ 62,632
Unpaid principal balance, with no related allowance	65,689
Unpaid Principal Balance	128,321	$ 125,098
Real estate - commercial mortgage
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	15,145
Unpaid principal balance, with no related allowance	25,781
Unpaid Principal Balance	40,926	33,166
Commercial
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	14,326
Unpaid principal balance, with no related allowance	20,948
Unpaid Principal Balance	35,274	48,106
Real estate - residential mortgage
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	23,637
Unpaid principal balance, with no related allowance	1,256
Unpaid Principal Balance	24,893	16,676
Construction
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	607
Unpaid principal balance, with no related allowance	1,014
Unpaid Principal Balance	1,621	3,618
Real-estate - home equity
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	8,682
Unpaid principal balance, with no related allowance	0
Unpaid Principal Balance	8,682	7,004
Consumer
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	235
Unpaid principal balance, with no related allowance	0
Unpaid Principal Balance	235	0
Equipment lease financing, other and overdrafts
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	0
Unpaid principal balance, with no related allowance	16,690
Unpaid Principal Balance	$ 16,690	$ 16,528

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

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