Acquisitions - Pro Forma Summary of All Acquisitions (Details) - USD ($) $ / shares in Units, $ in Millions |
12 Months Ended | |
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Dec. 31, 2018 |
Dec. 31, 2017 |
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| Business Combinations [Abstract] | ||
| Revenue | $ 12,021.6 | $ 12,039.9 |
| Net income | $ 264.4 | $ 248.9 |
| Basic net income per share (in dollars per share) | $ 10.85 | $ 9.93 |
| Diluted net income per share (in dollars per share) | $ 10.81 | $ 9.90 |
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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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