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Acquisitions - Business Acquisition, Pro Forma Information (Details) - Bank of the Cascades - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Business Acquisition [Line Items] |  |  |  |
Interest income | $ 121.2 | $ 108.7 | $ 341.8 | $ 312.1
Non-interest income | 36.2 | 38.3 | 109.0 | 116.2
Total revenues | 157.4 | 147.0 | 450.8 | 428.3
Net income | $ 41.4 | $ 34.9 | $ 119.8 | $ 94.0
EPS - basic (in dollars per share) | $ 0.71 | $ 0.52 | $ 2.10 | $ 1.55
EPS - diluted (in dollars per share) | $ 0.71 | $ 0.51 | $ 2.09 | $ 1.53

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