BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - SUMMARY OF REVENUE DISAGGREGATED BY SOURCE AND GEOGRAPHY (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 118.0	$ 125.2
Property lease revenue	1,875.1	1,688.2
Total operating revenues	1,993.1	1,813.4
Non-lease property revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	98.1	97.8
Services revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	19.9	27.4
Total operating revenues	19.9	27.4
U.S.
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	78.5	86.2
Property lease revenue	1,031.3	927.5
Total operating revenues	1,109.8	1,013.7
U.S. \| Non-lease property revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	58.6	58.8
U.S. \| Services revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	19.9	27.4
Asia
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2.2	2.4
Property lease revenue	284.4	286.5
Total operating revenues	286.6	288.9
Asia \| Non-lease property revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2.2	2.4
Asia \| Services revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0.0	0.0
Africa
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2.9	0.8
Property lease revenue	222.6	143.2
Total operating revenues	225.5	144.0
Africa \| Non-lease property revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2.9	0.8
Africa \| Services revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0.0	0.0
Europe
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1.5	0.8
Property lease revenue	33.0	32.7
Total operating revenues	34.5	33.5
Europe \| Non-lease property revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1.5	0.8
Europe \| Services revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0.0	0.0
Latin America
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	32.9	35.0
Property lease revenue	303.8	298.3
Total operating revenues	336.7	333.3
Latin America \| Non-lease property revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	32.9	35.0
Latin America \| Services revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 0.0	$ 0.0

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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