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Loans - Major Classifications - Loan Concentrations (Details) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2015 | Dec. 31, 2014
Total real estate | Loan receivables | Customer concentration risk |  |
Loans |  |
Loans receivable as a percentage of total portfolio | 87.20% | 87.60%

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