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Share-Based Payments (Details 1) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	$ (55.8)	$ (49.5)	$ (128.4)	$ (118.8)
Subtotal	59.4	45.5	137.9	121.9
Capitalized share-based compensation costs	(1.7)	(1.5)	(4.3)	(3.0)
Share-based compensation expense included in total costs and expenses	57.7	44.0	133.6	118.9
Market stock units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	9.3	7.4	25.8	26.5
Time-vested restricted stock units
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	40.4	34.5	83.2	72.0
Cash settled performance shares
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	0.0	(0.1)	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	3.0	2.1	9.3	12.4
Performance stock units settled in cash
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	3.4	(4.0)	9.4	4.9
Employee stock purchase plan
Summary of share based compensation expense associated with different programs [Abstract]
Share-based compensation expense	$ 3.3	$ 5.6	$ 10.2	$ 7.9

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Share based compensation expense included in costs and expenses.

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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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