Acquisitions (Unaudited Pro Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Acquisitions [Abstract]
Revenue	$ 2,779	$ 5,322	$ 5,549
Operating income	385	743	733
Net loss attributable to Frontier common shareholders	$ (43)	$ (96)	$ (120)
Basic and diluted net loss attributable to Frontier common shareholders per share	$ (0.04)	$ (0.08)	$ (0.10)

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=56956515&loc=d3e1392-128463

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, 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 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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