Loans, Troubled Debt Restructurings Subsequent Default (Details)	12 Months Ended
Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	55	66	68
Recorded Investment \| $	$ 5,241	$ 3,879	$ 4,574
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	3	2	0
Recorded Investment \| $	$ 0	$ 0	$ 0
Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	20	36	44
Recorded Investment \| $	$ 3,553	$ 3,137	$ 4,102
Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	32	27	23
Recorded Investment \| $	$ 1,688	$ 735	$ 457
Other consumer
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	1	1
Recorded Investment \| $	$ 0	$ 7	$ 15

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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