Revenue from Contracts with Customers - Contract Assets and Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Contract Assets, Current [Roll Forward]
Balance as of beginning of fiscal year	$ 38.5	$ 51.2	$ 36.5
Recognized in current year	84.2	74.5	92.9
Reclassified to accounts receivable	(83.9)	(79.9)	(95.8)
Impairment	0.0	0.0	0.0
Reclassification to/from long-term	0.1	0.0	16.8
Divestiture	0.0	(7.3)	0.0
Other	0.0	0.0	0.8
Balance as of period end	38.9	38.5	51.2
Contract Assets, Noncurrent [Roll Forward]
Balance as of beginning of fiscal year	0.1	0.1	16.9
Recognized in current year	0.0	0.0	0.0
Reclassified to accounts receivable	0.0	0.0	0.0
Impairment	0.0	0.0	0.0
Reclassification to/from short-term	(0.1)	0.0	(16.8)
Balance as of period end	0.0	0.1	0.1
Contract Liabilities, Current [Roll Forward]
Balance as of beginning of fiscal year	78.7	71.4	69.7
Recognized in current year	170.3	126.1	76.7
Amounts in beginning balance reclassified to revenue	(54.9)	(49.2)	(49.6)
Current year amounts reclassified to revenue	(90.1)	(76.0)	(42.7)
Other	0.0	1.9	2.7
Reclassification to/from long-term	7.8	4.5	14.6
Balance as of period end	111.8	78.7	71.4
Contract Liabilities, Noncurrent [Roll Forward]
Balance as of beginning of fiscal year	25.9	7.3	22.2
Recognized in current year	14.9	24.2	0.7
Amounts in beginning balance reclassified to revenue	(1.0)	(1.1)	(1.0)
Current year amounts reclassified to revenue	0.0	0.0	0.0
Other	0.0	0.0	0.0
Reclassification to/from short-term	(7.8)	(4.5)	(14.6)
Balance as of period end	32.0	25.9	7.3
Amortization of contract costs	$ 1.4	$ 1.4	$ 1.2