Debt - Credit Facilities (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Proceeds from Issuance of Long-term Debt	$ 525.0	$ 0	$ 2,134.3
Line of credit facility, maximum borrowing capacity				125	150
Line of Credit Facility, Exception to Proceeds from Sales of Assets	25
Loss on extinguishment of debt	13.6	0	46.5
Debt Instrument, Basis Spread on Variable Rate	0.50%
Line of Credit Facility, Increase (Decrease), Other, Net	50
Line of Credit Facility, Commitment Fee Amount	1.6	2.3	2.3
Equity Interests in Foreign Subsidiaries	66.00%
Line of Credit Facility, Amount Outstanding	0	0
Debt Instrument, Interest Rate During Period	1.40%
Receivables program maximum capacity	105.0
Receivables facility, letters credit outstanding	6.3
Receivables facility remaining borrowing capacity	32.3
Receivables facility maximum borrowing capacity	90.6
Dividends, Cash	95.00%
Accounts Receivable Facility, Renewal Term	364
Receivables facility amount outstanding	52.0	0
Long-term Debt	2,689.4	2,533.6
LIBOR Rate Advances [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	3.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	4.25%
Debt Instrument, Basis Spread on Variable Rate	1.00%
Base Rate Advance [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	2.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	3.25%
Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	200
Standby Letters of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	30
Bridge Loan [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	25
Receivables Facilities [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Amount	0.7	0.7	0.6
Debt Instrument, Interest Rate, Stated Percentage	1.10%
Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Maximum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.625%
CyrusOne LP [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
CyrusOne LP [Member] | LIBOR Rate Advances [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.50%
CyrusOne LP [Member] | Base Rate Advance [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.50%
CyrusOne LP [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	225
CyrusOne LP [Member] | Standby Letters of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	50
CyrusOne LP [Member] | Bridge Loan [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 30