Goodwill, Intangible and Other Long-Lived Assets - Narrative (Details) - USD ($)	1 Months Ended	11 Months Ended	12 Months Ended
	Jan. 23, 2013	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Jul. 01, 2015
Business Acquisition [Line Items]
Goodwill			$ 453,400,000	$ 276,200,000
Impairment of long-lived and intangible assets			0	0
Impairment of goodwill			0	0
Amortization expense for intangible assets subject to amortization	$ 1,000,000	$ 15,900,000	18,500,000	$ 17,000,000
Cervalis
Business Acquisition [Line Items]
Goodwill					$ 177,200,000
Goodwill acquired			177,200,000
Cervalis | Customer relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			117,400,000
Cervalis | Trademark
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			2,300,000
Cervalis | Leases, Acquired-in-Place
Business Acquisition [Line Items]
Finite-lived intangible assets acquired			$ 200,000