Noncontrolling Interests - Operating Partnership (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 shares
Noncontrolling Interests - Operating Partnership
Redemption value of the noncontrolling interest \| $	$ 1,200,000
Closing price of the Company's stock (in dollars per share) \| $ / shares	$ 115.90
Noncontrolling Interests
Noncontrolling Interests - Operating Partnership
Reduction to noncontrolling interests in the Operating Partnership and an increase to common stock and additional paid in capital \| $	$ 11
Operating partnership
Noncontrolling Interests - Operating Partnership
Conversion ratio for common operating partnership units	1
Number of Operating Partnership Units (in shares)	48,163,870	48,016,645
Percentage of Total	100.00%	100.00%
Shares of common stock issued related to employee compensation arrangements	149,365
Quarterly distributions will receive by holders of operating partnership units (in dollars per unit) \| $ / shares	$ 1.22
Operating partnership \| Coresite Realty Corporation
Noncontrolling Interests - Operating Partnership
Number of Operating Partnership Units (in shares)	37,394,352	37,244,987
Percentage of Total	77.60%	77.60%
Operating partnership \| Noncontrolling interests
Noncontrolling Interests - Operating Partnership
Number of Operating Partnership Units (in shares)	10,769,518	10,771,658
Percentage of Total	22.40%	22.40%

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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).

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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.

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

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

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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.

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

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Number, before forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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