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Income Taxes - Quarter information (Detail) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Taxes
Effective tax rate of income (loss) before income taxes	22.20%		23.30%		19.50%	24.00%
Equity in net losses of unconsolidated entities	$ 14		$ 16		$ 40	$ 25
Excess tax benefits associated with equity-based compensation	2		5		23	17
Investment impairment				$ 52
Asset impairments	61
Landfill [Member]
Income Taxes
Asset impairments	20
Investments Qualifying for Federal Tax Credits [Member]
Income Taxes
Equity in net losses of unconsolidated entities	17		12		43	21
Income tax (expense) benefit, including tax credits, from equity method investment	17		18		41	33
Interest expense	$ 3		$ 2		6	$ 4
Refined Coal Facility [Member]
Income Taxes
Equity method investments impairment charges		$ 7			$ 7