BUSINESS COMBINATION - PROFORMA (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($) $ / shares shares
Pro-forma Combined
Operating revenue \| $	$ 1,974.2
Net income after income taxes \| $	$ 86.0
Basic Earnings Per Share (in dollars per share) \| $ / shares	$ 2.00
Diluted Earnings Per Share (in dollars per share) \| $ / shares	$ 1.98
Weighted Average Number of Shares Outstanding:
Basic \| shares	43.1
Diluted \| shares	43.5

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=79982066&loc=d3e1392-128463

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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

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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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