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Deposits (Tables) | 12 Months Ended
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Dec. 31, 2017
Deposits [Abstract] |
Schedule of Deposits, By Type | Deposits are summarized as follows:
December 31, | 2017 |  | 2016
Non-interest bearing demand | $ | 2,900.0 |  |  | $ | 1,906.3 |
Interest bearing: |  |  |
Demand | 2,787.5 |  |  | 2,276.5 |
Savings | 3,095.4 |  |  | 2,141.8 |
Time, $100 and over | 432.0 |  |  | 461.4 |
Time, other | 720.0 |  |  | 590.1 |
Total interest bearing | 7,034.9 |  |  | 5,469.8 |
Total deposits | $ | 9,934.9 |  |  | $ | 7,376.1 |
Schedule of Maturities of Time Deposits | Maturities of time deposits at December 31, 2017 are as follows:
| Time, $100 and Over |  | Total Time
Due within 3 months or less | $ | 88.6 |  |  | $ | 313.8 |
Due after 3 months and within 6 months | 65.3 |  |  | 167.3 |
Due after 6 months and within 12 months | 110.6 |  |  | 259.2 |
Due after 12 months | 167.5 |  |  | 411.6 |
Total | $ | 432.0 |  |  | $ | 1,151.9 |

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