v3.10.0.1

ACQUISITIONS AND DISPOSITIONS (Schedule of Acquisition) (Details) $ in Millions, $ in Millions	Apr. 17, 2018 USD ($)	Apr. 04, 2018 USD ($)	Feb. 28, 2018 USD ($)	Jan. 18, 2018 CAD ($)	Jan. 18, 2018 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)
Business Acquisition [Line Items]
Goodwill						$ 1,706.6	$ 1,719.1
Neutral Path
Business Acquisition [Line Items]
Cash	$ 0.7
Other current assets	0.2
Property and equipment	15.2
Intangibles	6.9
Goodwill	15.9
Deferred tax assets, net	1.5
Total assets acquired	40.4
Current liabilities	0.6
Deferred revenue	5.8
Total liabilities assumed	6.4
Net assets acquired	34.0
Net consideration paid	$ 33.3
McLean Data Center
Business Acquisition [Line Items]
Cash		$ 9.2
Property and equipment		0.6
Total assets acquired		9.8
Current liabilities		1.6
Other liabilities		8.2
Total liabilities assumed		9.8
Net consideration paid		$ (9.2)
Spread Networks
Business Acquisition [Line Items]
Cash			$ 1.5
Other current assets			4.2
Property and equipment			143.7
Intangibles			9.3
Goodwill			14.4
Deferred tax assets, net			7.1
Other assets			1.4
Total assets acquired			181.6
Current liabilities			2.6
Deferred revenue			27.2
Other liabilities			19.8
Total liabilities assumed			49.6
Net assets acquired			132.0
Net consideration paid			$ 130.5
Optic Zoo Networks
Business Acquisition [Line Items]
Cash					$ 1.4
Other current assets					0.4
Property and equipment					13.1
Intangibles					3.8
Goodwill					10.4
Other assets					0.2
Total assets acquired					29.3
Current liabilities					0.6
Deferred revenue					1.2
Deferred tax liabilities, net					1.3
Total liabilities assumed					3.1
Net assets acquired					26.2
Net consideration paid				$ 30.9	$ 24.8

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