Legal Proceedings (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Pending Litigation \| Kelly Logging Inc. v. First Interstate Bank
Loss Contingencies [Line Items]
Litigation Settlement, Expense	$ 5,000	$ 4,000

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.

No definition available.

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