Loans and Allowance for loan losses (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) contract	Dec. 31, 2014 USD ($) contract	Dec. 31, 2013 USD ($)
Financing Receivable, Modifications [Line Items]
Overdrafts reclassified as loans	$ 17	$ 12
Outstanding balances of related party loans	16,068	$ 17,339
New loans and advances from related party	2,252
Repayments from related party	$ 3,523
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0	0
Financing Receivable, Modifications, Number of Contracts \| contract		0
Other real estate owned	$ 1,965	$ 956	$ 1,451
Real Estate Acquired Through Foreclosure	1,965	$ 956
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Other real estate owned	0
Residential [Member]
Financing Receivable, Modifications [Line Items]
Other real estate owned	$ 0
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	2

Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479006&loc=d3e64164-112818

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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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

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(e))
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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-Subparagraph e
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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Reflects the amount of collections received from related parties to reduce the carrying amounts of loans and leases receivable due from them.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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