Reportable Operating Segments - Business Segments (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2016 location segment	Dec. 31, 2015 location segment
Reportable operating segments
Number of business segments \| segment	3	3
Retail Banking
Reportable operating segments
Number of banking locations \| location	62	62

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

No definition available.

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