Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2017

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Schedule Of Basic And Diluted Earnings Per Share

		Years Ended December 31,
In millions except per share amounts		2017		2016			2015
Basic earnings per share:
	Net income (loss)	$	(1,605)	$	(338)	$	180
	Less: undistributed earnings allocated to participating securities		-		-		6
	Net income (loss) available to common shareholders		(1,605)		(338)		174
	Basic weighted average shares (1)		118.9		133.0		163.9
	Net income (loss) per basic common share	$	(13.50)	$	(2.54)	$	1.06
Diluted earnings per share:
	Net income (loss)	$	(1,605)	$	(338)	$	180
	Less: undistributed earnings allocated to participating securities		-		-		6
	Net income (loss) available to common shareholders		(1,605)		(338)		174
	Basic weighted average shares (1)		118.9		133.0		163.9
	Effect of common stock equivalents:
	Stock options		-		-		1.0
	Diluted weighted average shares		118.9		133.0		164.9
	Net income (loss) per diluted common share	$	(13.50)	$	(2.54)	$	1.06
	Potentially dilutive securities excluded from the diluted EPS because of antidilutive affect		14.1		16.5		18.0
	(1) Includes 0.3 million, 0.9 million and 0.6 million of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend
	equivalents for the years ended December 31, 2017, 2016 and 2015, respectively.