Organization	9 Months Ended
Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Griffin Capital Essential Asset REIT, Inc., a Maryland corporation (the "Company"), was formed on August 28, 2008 under the Maryland General Corporation Law. The Company was organized primarily with the purpose of acquiring single tenant properties that are essential to the tenant’s business and used a substantial amount of the net proceeds from the Public Offerings (as defined below) to invest in these properties. The Company satisfied requisite financial and non-financial requirements and elected to be taxed as a REIT for each taxable year ended since December 31, 2010 and for each year thereafter. The Company’s year end is December 31. Griffin Capital Corporation, a California corporation (the "Sponsor"), has sponsored the Company’s Public Offerings. The Company’s Sponsor began operations in 1995, and was incorporated in 1996, to engage principally in acquiring and developing office and industrial properties. Kevin A. Shields, the Company's Chief Executive Officer and Chairman of the Company's board of directors, controls the Sponsor as the trustee of the trust entity that is the sole shareholder of the Sponsor. Griffin Capital Essential Asset Advisor, LLC, a Delaware limited liability company (the "Advisor"), was formed on August 27, 2008. Griffin Capital Asset Management Company, LLC ("GAMCO," formerly known as Griffin Capital REIT Holdings, LLC) is the sole member of the Advisor, and Griffin Capital, LLC ("GC") is the sole member of GAMCO. The Company has entered into an advisory agreement for the Public Offerings (as amended and restated, the "Advisory Agreement"), which states that the Advisor is responsible for managing the Company’s affairs on a day-to-day basis and identifying and making acquisitions and investments on behalf of the Company. The officers of the Advisor are also officers of the Sponsor. The Advisory Agreement has a one-year term, and it may be renewed for an unlimited number of successive one-year periods by the Company's board of directors. From 2009 to 2014, the Company offered shares of common stock, pursuant to a private placement offering to accredited investors (the "Private Offering") and two public offerings, consisting of an initial public offering and a follow-on offering (together, the "Public Offerings"), which included shares for sale, pursuant to the distribution reinvestment plan ("DRP"). The Company issued 126,592,885 total shares of its common stock for gross proceeds of approximately $1.3 billion, pursuant to the Private Offering and Public Offerings. On May 7, 2014, the Company filed a Registration Statement on Form S-3 with the SEC for the registration of $75.0 million in shares for sale pursuant to the DRP (the “2014 DRP Offering”). On September 22, 2015, the Company filed a Registration Statement on Form S-3 with the SEC for the registration of $100.0 million in shares for sale pursuant to the DRP (the “2015 DRP Offering” and together with the 2014 DRP Offering, the “DRP Offerings”) and terminated the 2014 DRP Offering. In connection with the DRP Offerings, the Company had issued 12,353,953 shares of the Company's common stock for gross proceeds of approximately $126.5 million through September 30, 2016. The 2015 DRP Offering may be terminated at any time upon 10 days’ prior written notice to stockholders. As of September 30, 2016, the Company had issued 180,713,806 shares of common stock and received aggregate gross offering proceeds of approximately $1.4 billion from the sale of shares in the Private Offering, the Public Offerings, and the DRP Offerings. There were 175,945,568 shares outstanding at September 30, 2016, including shares issued pursuant to the DRP, less shares redeemed pursuant to the share redemption program. As of September 30, 2016 and December 31, 2015, the Company had issued approximately $149.5 million and $110.2 million, respectively, in shares pursuant to the DRP, which are classified on the consolidated balance sheets as common stock subject to redemption, net of redemptions paid of approximately $47.2 million and $17.3 million, respectively, and redemptions payable totaling approximately $11.6 million and $6.3 million, respectively, which are included in accrued expenses and other liabilities on the consolidated balance sheets. See Note 13, Subsequent Events — Amendment to Share Redemption Program, for a discussion on the current status of the Company's share redemption program. Since inception and through September 30, 2016, the Company had redeemed 4,768,238 shares of common stock for approximately $47.2 million pursuant to the share redemption program. Griffin Capital Essential Asset Operating Partnership, L.P., a Delaware limited partnership (the "Operating Partnership"), was formed on August 29, 2008. The Operating Partnership owns, directly or indirectly, all of the properties that the Company has acquired. The Advisor purchased an initial 99% limited partnership interest in the Operating Partnership for $200,000, and the Company contributed the initial $1,000 capital contribution, received from the Advisor, to the Operating Partnership in exchange for a 1% general partner interest. As of September 30, 2016, the Company owned approximately 96% of the limited partnership units of the Operating Partnership, and, as a result of the contribution of five properties to the Company, the Sponsor and certain of its affiliates, including the Company’s Chief Executive Officer and Chairman, Kevin A. Shields, and certain officers of the Company, owned approximately 2% of the limited partnership units of the Operating Partnership. The remaining approximately 2% of the limited partnership units were owned by unaffiliated third parties. No limited partnership units of the Operating Partnership have been redeemed during the nine months ended September 30, 2016 and year ended December 31, 2015. The Operating Partnership may conduct certain activities through the Company’s taxable REIT subsidiary, Griffin Capital Essential Asset TRS, Inc., a Delaware corporation (the "TRS") formed on September 2, 2008, which is a wholly-owned subsidiary of the Operating Partnership. The TRS had no activity as of September 30, 2016. The Company’s property manager is Griffin Capital Essential Asset Property Management, LLC, a Delaware limited liability company (the “Property Manager”), which was formed on August 28, 2008 to manage the Company’s properties. The Property Manager derives substantially all of its income from the property management services it performs for the Company.

Organization

Griffin Capital Essential Asset REIT, Inc., a Maryland corporation (the "Company"), was formed on August 28, 2008 under the Maryland General Corporation Law. The Company was organized primarily with the purpose of acquiring single tenant properties that are essential to the tenant’s business and used a substantial amount of the net proceeds from the Public Offerings (as defined below) to invest in these properties. The Company satisfied requisite financial and non-financial requirements and elected to be taxed as a REIT for each taxable year ended since December 31, 2010 and for each year thereafter. The Company’s year end is December 31.

Griffin Capital Corporation, a California corporation (the "Sponsor"), has sponsored the Company’s Public Offerings. The Company’s Sponsor began operations in 1995, and was incorporated in 1996, to engage principally in acquiring and developing office and industrial properties. Kevin A. Shields, the Company's Chief Executive Officer and Chairman of the Company's board of directors, controls the Sponsor as the trustee of the trust entity that is the sole shareholder of the Sponsor.

Griffin Capital Essential Asset Advisor, LLC, a Delaware limited liability company (the "Advisor"), was formed on August 27, 2008. Griffin Capital Asset Management Company, LLC ("GAMCO," formerly known as Griffin Capital REIT Holdings, LLC) is the sole member of the Advisor, and Griffin Capital, LLC ("GC") is the sole member of GAMCO. The Company has entered into an advisory agreement for the Public Offerings (as amended and restated, the "Advisory Agreement"), which states that the Advisor is responsible for managing the Company’s affairs on a day-to-day basis and identifying and making acquisitions and investments on behalf of the Company. The officers of the Advisor are also officers of the Sponsor. The Advisory Agreement has a one-year term, and it may be renewed for an unlimited number of successive one-year periods by the Company's board of directors.

From 2009 to 2014, the Company offered shares of common stock, pursuant to a private placement offering to accredited investors (the "Private Offering") and two public offerings, consisting of an initial public offering and a follow-on offering (together, the "Public Offerings"), which included shares for sale, pursuant to the distribution reinvestment plan ("DRP"). The Company issued 126,592,885 total shares of its common stock for gross proceeds of approximately $1.3 billion, pursuant to the Private Offering and Public Offerings.

On May 7, 2014, the Company filed a Registration Statement on Form S-3 with the SEC for the registration of $75.0 million in shares for sale pursuant to the DRP (the “2014 DRP Offering”). On September 22, 2015, the Company filed a Registration Statement on Form S-3 with the SEC for the registration of $100.0 million in shares for sale pursuant to the DRP (the “2015 DRP Offering” and together with the 2014 DRP Offering, the “DRP Offerings”) and terminated the 2014 DRP Offering. In connection with the DRP Offerings, the Company had issued 12,353,953 shares of the Company's common stock for gross proceeds of approximately $126.5 million through September 30, 2016. The 2015 DRP Offering may be terminated at any time upon 10 days’ prior written notice to stockholders.

As of September 30, 2016, the Company had issued 180,713,806 shares of common stock and received aggregate gross offering proceeds of approximately $1.4 billion from the sale of shares in the Private Offering, the Public Offerings, and the DRP Offerings. There were 175,945,568 shares outstanding at September 30, 2016, including shares issued pursuant to the DRP, less shares redeemed pursuant to the share redemption program. As of September 30, 2016 and December 31, 2015, the Company had issued approximately $149.5 million and $110.2 million, respectively, in shares pursuant to the DRP, which are classified on the consolidated balance sheets as common stock subject to redemption, net of redemptions paid of approximately $47.2 million and $17.3 million, respectively, and redemptions payable totaling approximately $11.6 million and $6.3 million, respectively, which are included in accrued expenses and other liabilities on the consolidated balance sheets. See Note 13, Subsequent Events — Amendment to Share Redemption Program, for a discussion on the current status of the Company's share redemption program. Since inception and through September 30, 2016, the Company had redeemed 4,768,238 shares of common stock for approximately $47.2 million pursuant to the share redemption program.

Griffin Capital Essential Asset Operating Partnership, L.P., a Delaware limited partnership (the "Operating Partnership"), was formed on August 29, 2008. The Operating Partnership owns, directly or indirectly, all of the properties that the Company has acquired. The Advisor purchased an initial 99% limited partnership interest in the Operating Partnership for $200,000, and the Company contributed the initial $1,000 capital contribution, received from the Advisor, to the Operating Partnership in exchange for a 1% general partner interest. As of September 30, 2016, the Company owned approximately 96% of the limited partnership units of the Operating Partnership, and, as a result of the contribution of five properties to the Company, the Sponsor and certain of its affiliates, including the Company’s Chief Executive Officer and Chairman, Kevin A. Shields, and certain officers of the Company, owned approximately 2% of the limited partnership units of the Operating Partnership. The remaining approximately 2% of the limited partnership units were owned by unaffiliated third parties. No limited partnership units of the Operating Partnership have been redeemed during the nine months ended September 30, 2016 and year ended December 31, 2015. The Operating Partnership may conduct certain activities through the Company’s taxable REIT subsidiary, Griffin Capital Essential Asset TRS, Inc., a Delaware corporation (the "TRS") formed on September 2, 2008, which is a wholly-owned subsidiary of the Operating Partnership. The TRS had no activity as of September 30, 2016.

The Company’s property manager is Griffin Capital Essential Asset Property Management, LLC, a Delaware limited liability company (the “Property Manager”), which was formed on August 28, 2008 to manage the Company’s properties. The Property Manager derives substantially all of its income from the property management services it performs for the Company.