Acquisitions (Narrative) (Details) $ in Millions, kr in Billions				6 Months Ended
		Sep. 06, 2019 USD ($)	Sep. 06, 2019 SEK (kr)	Jun. 30, 2020 USD ($) item	Jun. 30, 2019 USD ($) item	Dec. 31, 2019 USD ($)
Acquisitions [Line Items]
Net cash paid				$ 7	$ 115
Goodwill				2,103		$ 2,096
Capital adjustments clawbacks				3
Acquisition-related Costs [Member]
Acquisitions [Line Items]
Pro forma financial information adjustment, quarterly interest expense				$ 1
Seven Tuck-In Control [Member]
Acquisitions [Line Items]
Number of Businesses Acquired | item				7
Net cash paid				$ 7
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					115
Goodwill					76
The 2019 Acquisitions [Member] | Trade Names [Member]
Acquisitions [Line Items]
Other intangibles related to acquisitions					4
The 2019 Acquisitions [Member] | Other Intangible Assets [Member]
Acquisitions [Line Items]
Other intangibles related to acquisitions					$ 44
Business Combinations, 2019 Acquisitions [Member]
Acquisitions [Line Items]
Number of Businesses Acquired | item					19
Pest Control Acquisition [Member]
Acquisitions [Line Items]
Contingent consideration				2
Net cash paid				24
Goodwill				8
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.