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Share-Based Payments (Details 1) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	$ (57.6)	$ (35.4)	$ (186.1)	$ (154.2)
Subtotal	62.1	39.6	200.0	161.5
Capitalized share-based compensation costs	(1.9)	(1.9)	(6.3)	(4.9)
Share-based compensation expense included in total costs and expenses	60.2	37.7	193.7	156.6
Market stock units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	9.7	5.5	35.5	32.0
Time-vested restricted stock units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	38.8	35.3	121.9	107.3
Cash settled performance shares
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	0.0	0.0	0.0	(1.7)
Performance units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	0.0	0.0	0.0	(0.1)
Performance stock units settled in stock
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	4.9	(8.4)	14.2	4.0
Performance stock units settled in cash
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	4.4	4.1	13.9	9.0
Employee stock purchase plan
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	$ 4.3	$ 3.1	$ 14.5	$ 11.0

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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