Fresh Start Accounting Reorganization Adjustments - Cumulative Effect of Emergence (Details) - USD ($) $ in Millions		6 Months Ended
	Jul. 01, 2019	Dec. 31, 2019	Jun. 30, 2019
Reorganizations [Abstract]
Gain on settlement of LSTC	$ 1,293
Debtor Reorganization Items, Legal and Advisory Professional Fees	(39)	$ 0	$ (39)
Reorganization Items, Net Gain on Reorganization	1,254
Fresh-start Adjustment, Increase/Decrease Reorganization Tax Items	(40)
Preconfirmation, Common Stock	1
Reorganization Items, Elimination of Predecessor Paid in Capital	526
Preconfirmation, Preferred and Common Stock Held in Treasury	(296)
Reorganization Items, Impact on Accumulated Deficit	$ 1,445