Consolidated Statement Of Equity - USD ($) shares in Thousands, $ in Millions	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Common Stock [Member]	Total
Balance at Dec. 31, 2015					$ (353)
Net loss							$ (186)
Other comprehensive income, net of tax							6
Balance at Mar. 31, 2016					(347)
Balance at Dec. 31, 2016		$ 298	$ 5,283	$ (460)	(387)	$ (215)	$ 4,519
Preferred Stock Balance (in shares) at Dec. 31, 2016	19,250
Common Stock Balance (in shares) at Dec. 31, 2016		1,192,986				(20,433)	1,172,553
Cumulative Effect Adjustment for the adoption of ASU 2016-09				1			$ 1
Stock plans			(69)			$ 67	(2)
Stock plans (in shares)						5,650
Dividends on common stock			(124)				(124)
Dividends on preferred stock			(54)				(54)
Net loss				(75)			(75)
Pension settlement costs, net of tax					25		25
Other comprehensive income, net of tax					36		36
Balance at Mar. 31, 2017		$ 298	$ 5,036	$ (534)	$ (326)	$ (148)	$ 4,326
Preferred Stock Balance (in shares) at Mar. 31, 2017	19,250
Common Stock Balance (in shares) at Mar. 31, 2017		1,192,986				(14,783)	1,178,203