Loans - Troubled Debt Restructurings (Details)	12 Months Ended
Dec. 31, 2016 USD ($) contract	Dec. 31, 2015 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract	8	7
Pre-modification outstanding recorded investment	$ 23,396,000	$ 7,074,000
Recorded investment	21,272,000	6,218,000
Troubled debt restructuring, paid off	$ 0
Allowance for loan losses, troubled debt restructurings		$ 35,000
Commercial & Industrial
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract	8	6
Pre-modification outstanding recorded investment	$ 23,396,000	$ 1,657,000
Recorded investment	$ 21,272,000	$ 862,000
Commercial real estate
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract		1
Pre-modification outstanding recorded investment		$ 5,417,000
Recorded investment		$ 5,356,000

Reflects the amount of troubled debt restructuring paid off.

No definition available.

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- Definition

Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

+ References

No definition available.

+ Details

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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.

+ Details

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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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- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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