ACQUISITIONS - NARRATIVE (Details) $ in Millions			3 Months Ended	9 Months Ended
	Aug. 30, 2019 USD ($) communications_site	May 30, 2019 USD ($) markets communications_site	Sep. 30, 2019 USD ($) communications_site	Sep. 30, 2019 USD ($) communications_site
Business Acquisition [Line Items]
Payment received related to acquisition in France				$ 13.1
Estimated aggregate impact of acquisitions completed, revenue			$ 5.3	7.9
Estimated aggregate impact of acquisitions completed, gross margin			$ 3.9	5.7
African Markets
Business Acquisition [Line Items]
Number of markets in which entity operates | markets		5
Eaton Towers Holding Limited
Business Acquisition [Line Items]
Percentage of interests acquired		100.00%
Eaton Towers Holding Limited | Communication Sites
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | communications_site		5,500
Purchase price		$ 1,850.0
U.S. Acquisition
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | communications_site	400
Aggregate purchase price	$ 483.9
Other Acquisitions 2019
Business Acquisition [Line Items]
Aggregate purchase price				$ 183.8
Other Acquisitions 2019 | Communication Sites
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | communications_site			582	582
ALLTEL Transaction
Business Acquisition [Line Items]
Aggregate purchase price	$ 43.0
ALLTEL Transaction | Towers
Business Acquisition [Line Items]
Number of communications sites acquired (in number of towers) | communications_site	243