Investment in Real Estate - Real Estate Investments and Intangibles and Related Depreciation and Amortization (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Investment in real estate
Buildings and improvements, cost	$ 1,786.3	$ 1,761.4
Equipment, cost	3,106.4	3,028.2
Buildings and improvements, accumulated depreciation	(567.1)	(545.1)
Equipment, accumulated depreciation	(902.4)	(834.1)
Buildings and improvements, net	1,219.2	1,216.3
Equipment, net	2,204.0	2,194.1
Intangible assets
Cost	400.5	403.6
Accumulated Depreciation and Amortization	(216.0)	(207.5)
Net book value	184.5	196.1
Customer relationships
Intangible assets
Cost	247.1	247.1
Accumulated Depreciation and Amortization	(154.1)	(151.1)
Net book value	93.0	96.0
In-place leases
Intangible assets
Cost	134.2	137.1
Accumulated Depreciation and Amortization	(51.9)	(46.7)
Net book value	82.3	90.4
Other contractual
Intangible assets
Cost	19.2	19.4
Accumulated Depreciation and Amortization	(10.0)	(9.7)
Net book value	$ 9.2	$ 9.7
Buildings
Intangible assets
Useful life of asset	30 years
Building improvements
Intangible assets
Useful life of asset	30 years
Equipment
Intangible assets
Useful life of asset	20 years

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Real Estate Investment Property. Accumulated Depreciation, Fixtures And Equipment

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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