The number of operating partnetship units of CyrusOne LP sold during the period.

No definition available.

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The number of partnership units of CyrusOne LP, the operating partnership, owned by the Company. These partnership units are exchangeable into shares of common stock of CyrusOne Inc. on a one-for-one basis.

+ References

No definition available.

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- Definition

Line items represent reporting 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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Fair value portion of investments accounted under the cost method.

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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.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Balance held at close of period in number of shares.

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This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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Dividends received on equity and other investments during the current period.

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The cash inflow associated with the sale of equity securities classified as available-for-sale securities.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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Investment in CyrusOne (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended					9 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Jan. 24, 2013
Investment [Line Items]
Investment owned in CyrusOne LP, Balance, Partnership Units									42.6
Dividends received from CyrusOne						$ 6.2	$ 19.5
Proceeds from sale of CyrusOne investment						181.2	596.3
Gain on sale of CyrusOne investment	$ 7.0	$ 33.3	$ 118.6	$ 117.7		151.9	412.9
Cost Method Investments, Fair Value Disclosure		$ 144.3				$ 144.3		$ 257.9
CyrusOne [Member]
Investment [Line Items]
Equity Method Investment, Ownership Percentage									69.00%
Investment Owned, Balance, Shares		3.0				3.0		6.9	1.9
Investment owned in CyrusOne LP, Balance, Partnership Units								6.3
Income (Loss) from Equity Method Investments				0.8			$ 5.2
Sale of Stock, Number of Shares Issued in Transaction	0.2	0.8	3.1
Proceeds from sale of CyrusOne investment	$ 8.0	$ 38.7	$ 142.5	170.3	$ 426.0
Gain on sale of CyrusOne investment				$ 117.7	$ 295.2
Equity Method Investment Sold, Partnership Units				6.0	14.3