Acquisitions (Unaudited Pro Forma Information) (Details) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($) $ / shares
Acquisitions [Abstract]
Revenue	$ 7,846
Operating income	1,129
Net loss attributable to Frontier common shareholders	$ (164)
Basic and diluted net loss per share attributable to Frontier common shareholders \| $ / 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=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 net Income or Loss for the period as if the business combination or combinations 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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