Debt and Other Financing Arrangements - Term Loans (Details)		12 Months Ended
	Oct. 01, 2018 USD ($)	Dec. 31, 2019 USD ($) covenant	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Line of Credit Facility [Line Items]
Borrowing capacity		$ 4,966,000,000
Maximum percentage of stock pledged		66.00%
Loss on extinguishment of debt		$ 0	$ 10,000,000	$ 1,000,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Loss on extinguishment of debt			$ 10,000,000	$ (1,000,000)
Line of Credit
Line of Credit Facility [Line Items]
Borrowing capacity	$ 4,900,000,000
Financing fees		$ 8,000,000
Number of debt covenants | covenant		2
Line of Credit | Revolving Credit Facility
Line of Credit Facility [Line Items]
Borrowing capacity	$ 1,500,000,000
Debt term	5 years
Revolving Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Borrowing capacity	$ 1,500,000,000
Debt term	5 years
Term Loan A Facility
Line of Credit Facility [Line Items]
Debt term	5 years
Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Borrowing capacity	$ 1,700,000,000
Debt term	5 years
Term Loan B Facility
Line of Credit Facility [Line Items]
Borrowing capacity	$ 1,700,000,000
Debt term	7 years
Term Loan B Facility | Term Loan
Line of Credit Facility [Line Items]
Borrowing capacity	$ 1,700,000,000
Debt term	7 years
Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		3.0
New Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Consolidated fixed coverage ratio		2.00
LIBOR | Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Variable rate		1.75%
LIBOR | Term Loan B Facility | Term Loan
Line of Credit Facility [Line Items]
Variable rate	2.75%
LIBOR | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Variable rate		2.00%
Debt Covenant, Term 1 | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio	4.0
Debt Covenant, Term 1 | New Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio	4.50
Debt Covenant, Term 1 | LIBOR | Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Variable rate		1.50%
Debt Covenant, Term 1 | LIBOR | Term Loan B Facility | Term Loan
Line of Credit Facility [Line Items]
Variable rate	3.00%
Debt Covenant, Term 1 | LIBOR | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Variable rate		1.75%
Debt Covenant, Term 2 | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio	3.75
Debt Covenant, Term 2 | Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		1.5
Debt Covenant, Term 2 | New Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		4.25
Debt Covenant, Term 2 | LIBOR | Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Variable rate		1.25%
Debt Covenant, Term 2 | LIBOR | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Variable rate		1.50%
Debt Covenant, Term 3 | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio	3.5
Debt Covenant, Term 3 | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		1.5
Debt Covenant, Term 3 | New Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		4.00
Debt Covenant, Term 3 | LIBOR | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Variable rate		1.25%
Debt Covenant, Term 4 | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio	2.75
Debt Covenant, Term 4 | New Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		3.75
Consolidated interest coverage ratio		2.75
Debt Covenant, Term 5 | New Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		3.5
Maximum | Debt Covenant, Term 1 | Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		2.5
Maximum | Debt Covenant, Term 1 | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		3.0
Maximum | Debt Covenant, Term 2 | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		2.5
Minimum | Debt Covenant, Term 1 | Term Loan A Facility | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		1.5
Minimum | Debt Covenant, Term 1 | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		2.5
Minimum | Debt Covenant, Term 2 | Term Loan A, New Credit Facility [Member] | Term Loan
Line of Credit Facility [Line Items]
Consolidated net leverage ratio		1.5