Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	$ 68,603
No Related Allowance, Unpaid Principal Balance	68,595
Unpaid Principal Balance	137,198	$ 125,098
Real estate - commercial mortgage
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	19,909
No Related Allowance, Unpaid Principal Balance	31,561
Unpaid Principal Balance	51,470	33,166
Commercial - secured
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	13,937
No Related Allowance, Unpaid Principal Balance	18,056
Unpaid Principal Balance	31,993	48,106
Real estate - residential mortgage
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	24,590
No Related Allowance, Unpaid Principal Balance	1,517
Unpaid Principal Balance	26,107	16,676
Construction - commercial residential
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	437
No Related Allowance, Unpaid Principal Balance	958
Unpaid Principal Balance	1,395	3,618
Real estate - home equity
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	9,398
No Related Allowance, Unpaid Principal Balance	190
Unpaid Principal Balance	9,588	7,004
Consumer
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	332
No Related Allowance, Unpaid Principal Balance	0
Unpaid Principal Balance	332	0
Leasing and other and overdrafts
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	0
No Related Allowance, Unpaid Principal Balance	16,313
Unpaid Principal Balance	$ 16,313	$ 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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