Advances and Other Receivables, Net - Advances and Other Receivable Reserves (Details) - Reserves for Advances and Other Receivables - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2018	Jul. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance - beginning of period	$ 0
Provision and other additions	47
Write-offs	0
Balance - end of period	47	$ 0
Predecessor
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance - beginning of period	$ 297	284	$ 184
Provision and other additions		69	142
Write-offs		(56)	(42)
Balance - end of period		$ 297	$ 284