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Loans - Major Classifications - Loan Concentrations (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Dec. 31, 2016 | Oct. 28, 2016
Total real estate | Customer concentration risk |  |  |
Loans |  |  |
Loans receivable as a percentage of total portfolio |  | 79.70% |
Total real estate | Loan receivables | Customer concentration risk |  |  |
Loans |  |  |
Loans receivable as a percentage of total portfolio | 78.60% |  |
Talmer |  |  |
Loans |  |  |
Loans |  |  | $ 221.0

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