DESCRIPTION OF BUSINESS, BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) site in Thousands	9 Months Ended
Sep. 30, 2016 joint_venture	Apr. 21, 2016 site system
Concentration Risk [Line Items]
Number of joint ventures the Company has a controlling interest in (in joint ventures) \| joint_venture	2
Joint Venture, Ghana And Uganda
Concentration Risk [Line Items]
Ownership interest (as a percent)	51.00%
Noncontrolling interest, ownership percentage by noncontrolling owners (as a percent)	49.00%
Joint Venture, South Africa
Concentration Risk [Line Items]
Ownership interest (as a percent)	75.00%
Noncontrolling interest, ownership percentage by noncontrolling owners (as a percent)	25.00%
ATC, TIPL
Concentration Risk [Line Items]
Ownership interest (as a percent)	51.00%
Viom Transaction
Concentration Risk [Line Items]
Percentage of voting interest acquired (as a percent)		51.00%
Number of communications sites acquired (in number of towers) \| site		42
Distributed antenna systems acquired (systems) \| system		200

Number of Distributed Antenna Systems (DAS) sites acquired

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- Definition

Equity Method Investments, Number Of Joint Ventures With Controlling Interests

+ References

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- Definition

Number Of Communications Sites Acquired

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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