Goodwill and Other Intangible Assets - Goodwill (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Intangible assets
Goodwill	$ 6,532	$ 6,532	$ 6,430	$ 6,247
Increase in goodwill during the period		102
Goodwill impairment charges	27	27	6	$ 34
Intangible assets	1,088	1,088	1,118
Less: Accumulated amortization	(567)	(567)	(546)
Total	521	521	572
Customer and Supplier Relationships [Member]
Intangible assets
Intangible assets	906	906	949
Less: Accumulated amortization	(469)	(469)	(461)
Total	437	437	488
Non-compete Covenant [Member]
Intangible assets
Intangible assets	72	72	60
Less: Accumulated amortization	(36)	(36)	(24)
Total	36	36	36
Licenses Permits and Other [Member]
Intangible assets
Intangible assets	110	110	109
Less: Accumulated amortization	(62)	(62)	(61)
Total	48	48	$ 48
Energy and Environmental Services [Member]
Intangible assets
Goodwill impairment charges	17	17
Lamp Tracker Reporting Unit [Member]
Intangible assets
Goodwill impairment charges	$ 10	$ 10