Reorganization Adjustments - Liabilities Subject to Compromise (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jul. 01, 2019
Fresh-Start Adjustment [Line Items]
Liabilities Subject to Compromise	$ 3,664	$ 3,664
Repayment of 1st Lien Notes		(1,383)
Accounts payable	(49)	(49)
Pension and other post employment benefit obligations	(33)	(33)
Other	(7)	(18)
Other long-term liabilities		32
Total liabilities reinstated at emergence		(132)
Fair value of equity		(1,156)
Proceeds from the Rights Offerings		300
Total fair value of equity issued in exchange for debt		(856)
Gain on settlement of LSTC		1,293
Debt	3,420
Interest payable	99
Environmental reserve	43
Dividends payable to parent	$ 13
Continuing Operations
Fresh-Start Adjustment [Line Items]
Fair value of equity		$ (1,156)