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Condensed Financial Information (Parent Company Only) - Condensed Statements of Income (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Condensed Financial Statements, Captions |  |  |
Salaries and benefits | $ 173.7 | $ 155.3 | $ 146.4
Interest expense | 26.6 | 59.0 | 40.9
Acquisition related expenses | 0.0 | 20.3 | 12.4
Earnings before income tax benefit | 209.3 | 235.1 | 206.3
Income tax benefit | 48.1 | 54.1 | 46.1
Net income | 161.2 | 181.0 | 160.2
Parent Company |  |  |
Condensed Financial Statements, Captions |  |  |
Dividends from subsidiaries | 130.0 | 178.0 | 148.5
Other interest income | 0.1 | 0.3 | 0.1
Other income, primarily management fees from subsidiaries | 28.7 | 25.9 | 17.0
Total income | 158.8 | 204.2 | 165.6
Salaries and benefits | 31.5 | 34.2 | 25.3
Interest expense | 6.6 | 4.7 | 4.5
Acquisition related expenses | 0.0 | 17.0 | 8.1
Other operating expenses, net | 15.6 | 14.8 | 14.5
Total expenses | 53.7 | 70.7 | 52.4
Earnings before income tax benefit | 105.1 | 133.5 | 113.2
Income tax benefit | (6.1) | (11.9) | (9.3)
Income before undistributed earnings of subsidiaries | 111.2 | 145.4 | 122.5
Undistributed earnings of subsidiaries | 50.0 | 35.6 | 37.7
Net income | $ 161.2 | $ 181.0 | $ 160.2

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