Long-Term Debt Long-Term Debt - Schedule of Long-Term Debt - Footnotes (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt issuance costs, net in other assets	[1]	$ 42	$ 47

[1] Unamortized deferred financing costs of $42 million and $47 million as of June 30, 2019 and December 31, 2018, respectively, related to the Company's revolving credit facilities are included in other assets, net in the accompanying condensed consolidated balance sheets.