Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Capital Lease Obligations, Current	$ 35.3	$ 25.8
Capital Lease Obligations, Noncurrent	121.5	121.3
Other Long-term Debt, Current	1.8	1.6
Other Long-term Debt, Noncurrent	56.1	57.8
Long-term Debt and Lease Obligation, Current	340.7	50.2
Long-term Debt and Lease Obligation	3,532.9	2,984.1
Long-Term Debt, Maturity, Year One	304.0
Long-Term Debt, Maturity, Year Two	4.0
Long-Term Debt, Maturity, Year Three	304.0
Long-Term Debt, Maturity, Year Four	4.0
Long-Term Debt, Maturity, Year Five	2,084.0
2018 Revolver [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	0.0	800.0
Long-term Debt	0.0	0.0
Senior Unsecured Notes Due 2021 [Member] [Domain]
Debt Instrument [Line Items]
Long-term Debt	299.7	0.0
Unsecured Long-term Debt, Noncurrent	$ 0.0	299.1
Debt Instrument, Description of Variable Rate Basis	three-month LIBOR, as determined in the case of the initial interest period, on May 25, 2018, and thereafter at the beginning of each quarterly period as described herein, plus 0.80 basis points
Secured Debt Term B [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 385.7	0.0
Long-term Debt	$ 3.9	0.0
Senior Unsecured Notes Due 2023 [Member] [Domain]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Long-term Debt	$ 0.0	0.0
Unsecured Long-term Debt, Noncurrent	$ 298.8	298.3
Senior Unsecured Notes Due 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.60%
Long-term Debt	$ 0.0	0.0
Unsecured Long-term Debt, Noncurrent	694.6	694.1
Senior Secured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 298.1	297.8
Debt Instrument, Interest Rate, Stated Percentage	3.85%
Long-term Debt	$ 0.0	0.0
Secured Debt Term A [Member]
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	0.0	415.7
Long-term Debt	0.0	22.8
Senior Secured Notes Due 2025
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 493.9	0.0
Debt Instrument, Interest Rate, Stated Percentage	5.50%
Long-term Debt	$ 0.0	0.0
Senior Secured Second Lien Notes Due 2025
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 1,184.2	0.0
Debt Instrument, Interest Rate, Stated Percentage	750.00%
Long-term Debt	$ 0.0	$ 0.0