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Acquisitions (Details) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Mar. 08, 2013 USD ($) | Dec. 31, 2015 USD ($) Branch | Dec. 31, 2014 USD ($)
Business Acquisition [Line Items] |  |  |
Goodwill acquired |  | $ 2,323 |
Alliance Financial Corporation [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Date of acquisition |  | Mar. 08, 2013 |
Total consideration paid | $ 226,000 |  |
Number of banking centers operated by acquiree | Branch |  | 26 |
Other goodwill adjustments [Abstract] |  |  |
Deferred tax adjustments |  |  | $ (1,000)
Valuation adjustments |  |  | (400)
Decrease in goodwill |  |  | $ (1,400)
Third Party Administrators, Inc. [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Total consideration paid |  | $ 4,100 |
Goodwill acquired |  | $ 2,300 |

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