Recent Accounting Pronouncements (Tables)

12 Months Ended

Dec. 31, 2019

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Summary Of Information About In Adoption Of ASU 2019-12

	Three Months Ended								Six Months Ended			Nine Months  Ended
In millions, except per share amounts	March 31, 2019			June 30, 2019			September 30, 2019		June 30,  2019			September 30,  2019
Provision (benefit) for income taxes as previously reported	$	(2	)	$	(37	)	$	18	$	(39	)	$	(21	)
Provision (benefit) for income taxes as revised		2			—			6		2			8
Net income (loss) as previously reported		(17	)		(170	)		71		(187	)		(116	)
Net income (loss) as revised		(21	)		(207	)		83		(228	)		(145	)
Net income (loss) per common share:
Basic—as previously reported	$	(0.20	)	$	(2.02	)	$	0.86	$	(2.20	)	$	(1.40	)
Basic—as revised		(0.24	)		(2.45	)		1.00		(2.68	)		(1.75	)
Diluted—as previously reported		(0.20	)		(2.02	)		0.86		(2.20	)		(1.40	)
Diluted—as revised		(0.24	)		(2.45	)		1.00		(2.68	)		(1.75	)