Consolidated Statements of Cash Flows - Supplemental Information - USD ($) $ in Millions	Dec. 31, 2019		Dec. 31, 2018		Aug. 01, 2018	Jul. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Statement of Cash Flows [Abstract]
Cash and cash equivalents	$ 329		$ 242			$ 166		$ 215
Restricted cash	283		319			430		360
Total cash, cash equivalents and restricted cash	$ 612	[1]	$ 561	[1]	$ 1,623	$ 596	[1]	$ 575	[1]	$ 877

[1] The following table provides a reconciliation of cash, cash equivalents and restricted cash to amount reported within the consolidated balance sheets. Successor Predecessor December 31, 2019 December 31, 2018 July 31, 2018 December 31, 2017Cash and cash equivalents$329 $242 $166 $215Restricted cash283 319 430 360Total cash, cash equivalents and restricted cash$612 $561 $596 $575