Acquisition - Pro Forma Financial Information (Details) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($) $ / shares
Business Combinations [Abstract]
Operating Revenues \| $	$ 5,878.8
Net Income \| $	$ 664.9
Earnings per share (Basic) \| $ / shares	$ 2.11
Earnings per share (Diluted) \| $ / shares	$ 2.10

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/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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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.

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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.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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No definition available.

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