Redemption of noncontrolling interests, shares.

No definition available.

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- Definition

Represents the ownership percentage expressed as a percentage.

+ References

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.

+ Details

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- Definition

Represents the number of units held in the Operating Partnership.

+ References

No definition available.

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- Definition

Represents the number of preferred Operating Partnership units issued to the entity.

+ References

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569655-111683

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4616395-111683

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- Definition

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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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- Definition

The aggregate fair value as of the reporting date of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
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-Section S99
-Paragraph 3A
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-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (12)(c)
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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- Details

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- Details

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Noncontrolling Interests - Operating Partnership (Details) $ / shares in Units, $ in Thousands			3 Months Ended			12 Months Ended
	Dec. 30, 2016 $ / shares	Dec. 12, 2012 shares	Sep. 30, 2016 $ / shares	Jun. 30, 2016 $ / shares	Mar. 31, 2016 $ / shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) shares
Noncontrolling Interests - Operating Partnership
Conversion ratio for common operating partnership units						1
Series A Cumulative Preferred Stock, dividend rate (as a percent)						7.25%	7.25%
Number of Operating Partnership Units (in shares)						47,227,915	46,994,903
Percentage of Total						100.00%	100.00%
Shares of common stock issued related to employee compensation arrangements						233,012
Coresite Realty Corporation
Noncontrolling Interests - Operating Partnership
Number of Operating Partnership Units (in shares)						33,376,568	30,136,556
Percentage of Total						70.70%	64.10%
Noncontrolling Interests
Noncontrolling Interests - Operating Partnership
Number of Operating Partnership Units (in shares)						13,851,347	16,858,347
Percentage of Total						29.30%	35.90%
Reduction to noncontrolling interests in the Operating Partnership and an increase to common stock and additional paid in capital \| $						$ 37,374	$ 110,180
Operating partnership
Noncontrolling Interests - Operating Partnership
Preferred Operating Partnership units issued to CoreSite Realty Corporation (in shares)		4,600,000
Series A Cumulative Preferred Stock, dividend rate (as a percent)		7.25%
Percentage of Total						70.70%
Percentage of Total						29.30%
Quarterly distributions will receive by holders of operating partnership units (in dollars per unit) \| $ / shares	$ 0.80		$ 0.53	$ 0.53	$ 0.53
Common Operating Partnership units redeemed for common stock (in shares)						3,007,000	8,500,000
Redemption of noncontrolling interests (in shares)						3,007,000	8,500,000
Reduction to noncontrolling interests in the Operating Partnership and an increase to common stock and additional paid in capital \| $						$ 37,400	$ 110,200
Operating partnership \| Noncontrolling Interests
Noncontrolling Interests - Operating Partnership
Redemption value of the noncontrolling interests \| $						$ 1,100,000
Closing price of the Company's stock (in dollars per share) \| $ / shares						$ 79.37