Acquisitions (Unaudited Pro Forma Information) (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) $ / shares
Acquisitions [Abstract]
Revenue	$ 2,714
Operating income	305
Net loss attributable to Frontier common shareholders	$ (95)
Basic and diluted net loss attributable to Frontier common shareholders per share \| $ / shares	$ (0.08)

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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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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