Noncontrolling Interests - Operating Partnership (Details) $ / shares in Units, $ in Billions	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 shares
Noncontrolling Interests - Operating Partnership
Redemption value of the noncontrolling interest \| $	$ 1.2
Closing price of the Company's stock (in dollars per share) \| $ / shares	$ 107.02
Operating partnership
Noncontrolling Interests - Operating Partnership
Conversion ratio for common operating partnership units	1
Number of Operating Partnership Units (in shares)	47,984,605	47,831,300
Percentage of Total	100.00%	100.00%
Shares of common stock issued related to employee compensation arrangements	153,305
Quarterly distributions will receive by holders of operating partnership units (in dollars per unit) \| $ / shares	$ 1.10
Operating partnership \| Coresite Realty Corporation
Noncontrolling Interests - Operating Partnership
Number of Operating Partnership Units (in shares)	36,409,337	36,256,032
Percentage of Total	75.90%	75.80%
Operating partnership \| Noncontrolling interests
Noncontrolling Interests - Operating Partnership
Number of Operating Partnership Units (in shares)	11,575,268	11,575,268
Percentage of Total	24.10%	24.20%

Represents the ownership percentage expressed as a percentage.

No definition available.

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- Definition

Represents the ratio for conversion of Operating Partnership units held by noncontrolling interests into common stock at the option of the entity.

+ References

No definition available.

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Represents the number of units held in the Operating Partnership.

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No definition available.

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- Definition

Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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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.

+ References

No definition available.

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

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No definition available.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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- Definition

Redemption value, as if currently redeemable, of redeemable noncontrolling interest classified as temporary equity and the election has been made to accrete changes in redemption value to the earliest redemption date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
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-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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