Acquisitions (Narrative) (Details) $ in Millions, kr in Billions				3 Months Ended
		Sep. 06, 2019 USD ($)	Sep. 06, 2019 SEK (kr)	Mar. 31, 2020 USD ($) item	Mar. 31, 2019 USD ($) item	Dec. 31, 2019 USD ($)
Acquisitions [Line Items]
Net cash paid				$ 6	$ 100
Goodwill				2,095		$ 2,096
Acquisition-related Costs [Member]
Acquisitions [Line Items]
Pro forma financial information adjustment, quarterly interest expense				$ 1
Five Tuck-In Control [Member]
Acquisitions [Line Items]
Number of Businesses Acquired | item				5
Net cash paid				$ 6
Two Pest Control [Member]
Acquisitions [Line Items]
Number of Businesses Acquired | item				2
Net cash paid				$ 18
The 2019 Acquisitions [Member]
Acquisitions [Line Items]
Net cash paid					$ 100
Goodwill				60
The 2019 Acquisitions [Member] | Trade Names [Member]
Acquisitions [Line Items]
Other intangibles related to acquisitions				4
The 2019 Acquisitions [Member] | Other [Member]
Acquisitions [Line Items]
Other intangibles related to acquisitions				36
Business Combinations, 2019 Acquisitions [Member]
Acquisitions [Line Items]
Number of Businesses Acquired | item					11
Asset Acquisitions, 2019 Acquisitions [Member]
Acquisitions [Line Items]
Number of Businesses Acquired | item					2
Pest Control Acquisition [Member]
Acquisitions [Line Items]
Contingent consideration				2
Net cash paid				26
Goodwill				7
Minority Investment [Member] | Accrued Liabilities - Unfunded [Member]
Acquisitions [Line Items]
Minority interest				$ 7
Nomor [Member]
Acquisitions [Line Items]
Cash Acquired from Acquisition		$ 9
Net cash paid		198	kr 2
Goodwill		127
Proceeds from revolving credit facility		120
Other intangibles related to acquisitions	[1]	$ 94
Minimum [Member] | Pest Control Acquisition [Member]
Acquisitions [Line Items]
Contingent consideration, term				1 year
Maximum [Member] | Pest Control Acquisition [Member]
Acquisitions [Line Items]
Contingent consideration, term				3 years

[1] Primarily customer lists.