Debt - Bridge Facility (Details)		1 Months Ended
	Mar. 27, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Feb. 28, 2017 USD ($)
Line of Credit Facility [Line Items]
Debt issuance costs, net		$ 67,900,000			$ 83,600,000	$ 33,700,000
Line of Credit
Line of Credit Facility [Line Items]
Debt issuance costs, net		$ 3,900,000
Bridge Loan Facility
Line of Credit Facility [Line Items]
Secured bridge agreement term	364 days	364 days
Maximum borrowing capacity	$ 615,000,000.0
Debt instrument, basis spread increase on variable rate ninety days following closing date	0.50%
Debt instrument, basis spread increase on variable rate end of each ninety day period thereafter	0.50%
Reference amount, percentage	50.00%
Fee	0.50%
Debt issuance costs, net	$ 6,200,000	$ 3,100,000			0
Line of credit facility covenant, total indebtedness, convertible debt excluded, maximum		$ 700,000,000
Interest rate spread on overdue amounts in event of default		2.00%
Bridge Loan Facility | Leverage Ratio Percent One
Line of Credit Facility [Line Items]
Line of credit facility, covenant, total leverage ratio, maximum	6.00
Bridge Loan Facility | Leverage Ratio Percent Two
Line of Credit Facility [Line Items]
Line of credit facility, covenant, total leverage ratio, maximum	4.75
Bridge Loan Facility | Leverage Ratio Percent Three
Line of Credit Facility [Line Items]
Line of credit facility, covenant, total leverage ratio, maximum	3.25
Bridge Loan Facility | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.75%
Bridge Loan Facility | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.75%
Revolving Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 3,570,000,000	$ 3,570,000,000	$ 3,600,000,000
Debt issuance costs, net		14,600,000			$ 14,700,000
Line of credit facility covenant, total indebtedness, convertible debt excluded, maximum		$ 700,000,000
Interest rate spread on overdue amounts in event of default		2.00%
Revolving Credit Facility | Line of Credit | Leverage Ratio Percent One
Line of Credit Facility [Line Items]
Line of credit facility, covenant, total leverage ratio, maximum		6.00
Revolving Credit Facility | Line of Credit | Leverage Ratio Percent Two
Line of Credit Facility [Line Items]
Line of credit facility, covenant, total leverage ratio, maximum		5.75
Revolving Credit Facility | Line of Credit | Leverage Ratio Percent Three
Line of Credit Facility [Line Items]
Line of credit facility, covenant, total leverage ratio, maximum		5.25