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Condensed Financial Information (Parent Company Only) - Condensed Statements of Income (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2018 | Sep. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Condensed Financial Statements, Captions |  |  |  |  |
Salaries and benefits |  |  | $ 155.3 | $ 146.4 | $ 122.7
Interest expense |  |  | 59.0 | 40.9 | 28.0
Acquisition related expenses |  | $ 12.4 | 20.3 | 12.4 | 27.2
Earnings before income tax benefit |  |  | 235.1 | 206.3 | 156.7
Income tax benefit |  |  | 54.1 | 46.1 | 50.2
Net income | $ 160.2 |  | 181.0 | 160.2 | 106.5
Parent Company |  |  |  |  |
Condensed Financial Statements, Captions |  |  |  |  |
Dividends from subsidiaries |  |  | 178.0 | 148.5 | 150.0
Other interest income |  |  | 0.3 | 0.1 | 0.1
Other income, primarily management fees from subsidiaries |  |  | 25.9 | 17.0 | 18.0
Total income |  |  | 204.2 | 165.6 | 168.1
Salaries and benefits |  |  | 34.2 | 25.3 | 21.8
Interest expense |  |  | 4.7 | 4.5 | 4.7
Acquisition related expenses |  |  | 17.0 | 8.1 | 25.3
Other operating expenses, net |  |  | 14.8 | 14.5 | 13.0
Total expenses |  |  | 70.7 | 52.4 | 64.8
Earnings before income tax benefit |  |  | 133.5 | 113.2 | 103.3
Income tax benefit |  |  | (11.9) | (9.3) | (14.2)
Income before undistributed earnings of subsidiaries |  |  | 145.4 | 122.5 | 117.5
Undistributed earnings of subsidiaries |  |  | 35.6 | 37.7 | (11.0)
Net income |  |  | $ 181.0 | $ 160.2 | $ 106.5

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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460 + Details
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