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Acquisitions - Business Acquisition, Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Business Combinations [Abstract] |  |  |  |
Pro Forma Acquisition Expenses, Net of Tax | $ 10.7 |  | $ 11.2 |
Interest income | 113.0 | $ 103.3 | 220.6 | $ 203.3
Non-interest income | 37.7 | 41.3 | 72.9 | 77.9
Total revenues | 150.7 | 144.6 | 293.5 | 281.2
Net income | $ 41.7 | $ 29.4 | $ 79.9 | $ 58.7
EPS - basic (in dollars per share) | $ 0.74 | $ 0.50 | $ 1.42 | $ 1.02
EPS - diluted (in dollars per share) | $ 0.74 | $ 0.50 | $ 1.41 | $ 1.01

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