Net Loss Per Share (Calculation Of Net Income (Loss) Per Common Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net Loss Per Share [Abstract]
Net loss attributable to Frontier common shareholders, Basic	$ (80)	$ (28)	$ (320)	$ (79)
Less: Dividends paid on unvested restricted stock awards	(1)		(2)	(1)
Total basic and diluted net loss attributable to Frontier common shareholders	$ (81)	$ (28)	$ (322)	$ (80)
Total weighted average shares and unvested restricted stock awards outstanding - basic (in shares)	1,172,973	1,044,531	1,171,560	1,026,278
Less: Weighted average unvested restricted stock awards (in shares)	(8,711)	(7,124)	(7,477)	(7,302)
Total weighted average shares outstanding - basic (in shares)	1,164,262	1,037,407	1,164,083	1,018,976
Basic net loss per share attributable to Frontier common shareholders	$ (0.07)	$ (0.03)	$ (0.28)	$ (0.08)
Total weighted average shares outstanding - diluted (in shares)	1,164,262	1,037,407	1,164,083	1,018,976
Diluted net loss per share attributable to Frontier common shareholders	$ (0.07)	$ (0.03)	$ (0.28)	$ (0.08)