Loans, Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($) loan	Sep. 30, 2018 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	67	71
Recorded Investment(a)	$ 7,500	$ 10,138
Unpaid Principal Balance(b)	$ 7,577	$ 10,353
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	1	6
Recorded Investment(a)	$ 185	$ 1,954
Unpaid Principal Balance(b)	$ 185	$ 1,995
Commercial real estate — investor
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	1
Recorded Investment(a)	$ 0	$ 958
Unpaid Principal Balance(b)	$ 0	$ 1,022
Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	47	29
Recorded Investment(a)	$ 6,785	$ 5,655
Unpaid Principal Balance(b)	$ 6,863	$ 5,733
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	18	32
Recorded Investment(a)	$ 520	$ 1,552
Unpaid Principal Balance(b)	$ 520	$ 1,582
Other consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	1	3
Recorded Investment(a)	$ 9	$ 19
Unpaid Principal Balance(b)	$ 9	$ 21

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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