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Debt and Other Financing Arrangements - Summary of Long-Term Debt Obligations (Details)	Jun. 30, 2021 USD ($)	Jun. 30, 2021 EUR (€)	Mar. 17, 2021 USD ($)	Mar. 03, 2021	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Carrying amount	$ 5,088,000,000				$ 5,176,000,000
Less - maturities classified as current	7,000,000				5,000,000
Total long-term debt	5,081,000,000				5,171,000,000
Unamortized debt issuance costs	87,000,000				82,000,000
Debt discount	1,000,000
Unamortized premium					(20,000,000)
Revolver Borrowings \| Due 2023
Debt Instrument [Line Items]
Principal	0				0
Carrying amount	0				0
Term Loans \| A2.00 Term Loan A Due 2019 Through 2023
Debt Instrument [Line Items]
Principal	1,466,000,000				1,530,000,000
Carrying amount	$ 1,458,000,000				$ 1,520,000,000
Stated rate	2.00%	2.00%
Term Loans \| A2.00 Term Loan A Due 2019 Through 2023 \| LIBOR
Debt Instrument [Line Items]
Stated rate					2.50%
Term Loans \| 3.00% Term Loan B Due 2019 Through 2025
Debt Instrument [Line Items]
Principal	$ 1,658,000,000				$ 1,666,000,000
Carrying amount	$ 1,609,000,000				1,612,000,000
Stated rate	3.00%	3.00%
Senior Notes \| 5.375% Senior Notes due 2024
Debt Instrument [Line Items]
Principal	$ 225,000,000	€ 225,000,000			225,000,000
Carrying amount	$ 223,000,000				223,000,000
Stated rate	5.375%	5.375%
Senior Notes \| 5.000% Senior Notes due 2026
Debt Instrument [Line Items]
Principal	$ 500,000,000	€ 500,000,000			500,000,000
Carrying amount	$ 495,000,000				494,000,000
Stated rate	5.00%	5.00%
Senior Notes \| Euro Floating Rate Notes due 2024
Debt Instrument [Line Items]
Principal	$ 0	€ 300,000,000			366,000,000
Carrying amount	$ 0				370,000,000
Stated rate	4.875%	4.875%
Senior Notes \| 5.000% Euro Fixed Rate Notes due 2024
Debt Instrument [Line Items]
Principal	$ 0	€ 350,000,000			428,000,000
Carrying amount	$ 0				445,000,000
Stated rate	5.00%	5.00%		5.00%
Senior Notes \| 7.875% Senior Secured Notes Due 2029
Debt Instrument [Line Items]
Principal	$ 500,000,000				500,000,000
Carrying amount	$ 490,000,000				489,000,000
Stated rate	7.875%	7.875%
Senior Notes \| 5.125% Senior Secured Notes Due 2029
Debt Instrument [Line Items]
Principal	$ 800,000,000		$ 800,000,000		0
Carrying amount	$ 786,000,000				0
Stated rate	5.125%	5.125%	5.125%
Other debt, primarily foreign instruments
Debt Instrument [Line Items]
Principal	$ 28,000,000				24,000,000
Carrying amount	$ 27,000,000				$ 23,000,000