Loans Loans Modified in Trouble Debt Restructurings (Details) - Entity Loan Modification Program - Payment Deferral $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract	Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	3	1	8	2
Pre-Modification Outstanding Recorded Investment	$ 750	$ 15	$ 1,279	$ 23
Post-Modification Outstanding Recorded Investment	$ 750	$ 15	$ 1,279	$ 23
Financing Receivable, Modification, Subsequent Default, Number of Contracts \| contract	0	0	0	0
Financing Receivable, Modification, Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0	$ 0
Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	1	0	2	0
Pre-Modification Outstanding Recorded Investment	$ 725	$ 0	$ 1,228	$ 0
Post-Modification Outstanding Recorded Investment	$ 725	$ 0	$ 1,228	$ 0
Financing Receivable, Modification, Subsequent Default, Number of Contracts \| contract	0	0	0	0
Financing Receivable, Modification, Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0	$ 0
Commercial Real Estate Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	0	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
Financing Receivable, Modification, Subsequent Default, Number of Contracts \| contract	0	0	0	0
Financing Receivable, Modification, Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0	$ 0
Consumer Loans Financing
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	2	1	6	2
Pre-Modification Outstanding Recorded Investment	$ 25	$ 15	$ 51	$ 23
Post-Modification Outstanding Recorded Investment	$ 25	$ 15	$ 51	$ 23
Financing Receivable, Modification, Subsequent Default, Number of Contracts \| contract	0	0	0	0
Financing Receivable, Modification, Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0	$ 0
Residential
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	0	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
Financing Receivable, Modification, Subsequent Default, Number of Contracts \| contract	0	0	0	0
Financing Receivable, Modification, Subsequent Default, Recorded Investment	$ 0	$ 0	$ 0	$ 0

Financing Receivable, Modification, Subsequent Default, Number of Contracts

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- Definition

Financing Receivable, Modification, Subsequent Default, Recorded Investment

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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- Definition

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