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
Net loss							$ (213)
Other comprehensive income, net of tax							11
Balance at Dec. 31, 2016		$ 20	$ 5,561	$ (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		79,532				(1,362)	78,170
Cumulative Effect Adjustment from adoption of ASU 2016-09				1			$ 1
Stock plans (in shares)						347
Stock plans			(64)			$ 68	4
Dividends on common stock			(172)				(172)
Dividends on preferred stock			(107)				(107)
Net loss				(737)			(737)
Pension settlement costs, net of tax					36		36
Other comprehensive income, net of tax					22		22
Balance at Jun. 30, 2017		$ 20	$ 5,218	$ (1,196)	$ (329)	$ (147)	$ 3,566
Preferred Stock Balance (in shares) at Jun. 30, 2017	19,250
Common Stock Balance (in shares) at Jun. 30, 2017		79,532				(1,015)	78,517