Related Party Transactions	9 Months Ended
Sep. 30, 2017
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Supervisory Fee Revenue We earned supervisory fees from entities affiliated with Anthony E. Malkin, our Chairman and Chief Executive Officer, of $0.3 million and $0.3 million for the three months ended September 30, 2017 and 2016, respectively, and $0.9 million and $1.1 million for the nine months ended September 30, 2017 and 2016, respectively. These fees are included within third-party management and other fees. Property Management Fee Revenue We earned property management fees from entities affiliated with Anthony E. Malkin of $0.1 million and $0.1 million for the three months ended September 30, 2017 and 2016, respectively, and $0.2 million and $0.3 million for the nine months ended September 30, 2017 and 2016, respectively. These fees are included within third-party management and other fees. Other We were reimbursed at allocable cost for 647 square feet of shared office space, equipment, and administrative support, as was done prior to our formation, and we received rent generally at market rental rate for 3,074 square feet of leased space, from entities affiliated with Anthony E. Malkin, at one of our properties aggregating $0.07 million and $0.2 million for the three and nine months ended September 30, 2016, respectively. During August 2016, such entities moved from the previously shared office and leased spaces to relocate to a new 5,351 square foot leased space at one of our properties, paying rent generally at a market rental rate. Under such new lease, the tenant has the right to cancel such lease without special payment on 90 days’ notice. We now have a shared use agreement with such tenant, to occupy a portion of the leased premises as the office location for Peter L. Malkin, our chairman emeritus and employee, utilizing approximately 15% of the space, for which we pay an allocable pro rata share of the cost to such tenant. We also have agreements with these entities to provide them with general computer-related support. Total revenue aggregated $0.1 million and $0.3 million for the three and nine months ended September 30, 2017, respectively. One of our directors, James D. Robinson IV, is a general partner in an investment fund, which owns more than a 10% economic and voting interest in one of our tenants, OnDeck Capital, with an annualized rent of $5.8 million and $5.7 million as of September 30, 2017 and 2016, respectively.

Related Party Transactions

Supervisory Fee Revenue

We earned supervisory fees from entities affiliated with Anthony E. Malkin, our Chairman and Chief Executive Officer, of $0.3 million and $0.3 million for the three months ended September 30, 2017 and 2016, respectively, and $0.9 million and $1.1 million for the nine months ended September 30, 2017 and 2016, respectively. These fees are included within third-party management and other fees.

Property Management Fee Revenue

We earned property management fees from entities affiliated with Anthony E. Malkin of $0.1 million and $0.1 million for the three months ended September 30, 2017 and 2016, respectively, and $0.2 million and $0.3 million for the nine months ended September 30, 2017 and 2016, respectively. These fees are included within third-party management and other fees.

Other

We were reimbursed at allocable cost for 647 square feet of shared office space, equipment, and administrative support, as was done prior to our formation, and we received rent generally at market rental rate for 3,074 square feet of leased space, from entities affiliated with Anthony E. Malkin, at one of our properties aggregating $0.07 million and $0.2 million for the three and nine months ended September 30, 2016, respectively.

During August 2016, such entities moved from the previously shared office and leased spaces to relocate to a new 5,351 square foot leased space at one of our properties, paying rent generally at a market rental rate. Under such new lease, the tenant has the right to cancel such lease without special payment on 90 days’ notice. We now have a shared use agreement with such tenant, to occupy a portion of the leased premises as the office location for Peter L. Malkin, our chairman emeritus and employee, utilizing approximately 15% of the space, for which we pay an allocable pro rata share of the cost to such tenant. We also have agreements with these entities to provide them with general computer-related support. Total revenue aggregated $0.1 million and $0.3 million for the three and nine months ended September 30, 2017, respectively.

One of our directors, James D. Robinson IV, is a general partner in an investment fund, which owns more than a 10% economic and voting interest in one of our tenants, OnDeck Capital, with an annualized rent of $5.8 million and $5.7 million as of September 30, 2017 and 2016, respectively.