Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2020
Principles of Consolidation
Third party out of pocket costs reimbursement (as a percent)		3.00%
Asset Retirement Obligations
Post-closure period for landfill to maintain and monitor		30 years
Income taxes
Income tax refund receivable as a result of the CARES Act	$ 55
Current income tax benefit	11
Previously recognized deferred income tax benefit	$ 44
Income tax refund received		$ 39