Impairment of Real Estate	12 Months Ended
Dec. 31, 2014
Impairment of Real Estate [Abstract]
Impairment of Real Estate Investments	Impairment of Real Estate Investments The Company assesses on a regular basis whether there are any indicators that the carrying value of real estate assets may be impaired. Potential indicators may include an increase in vacancy at a property, tenant reduction in utilization of a property, tenant financial instability and the potential sale of the property in the near future. An asset is determined to be impaired if the asset's carrying value is in excess of its estimated fair value. During 2014, 2013 and 2012, the Company recognized aggregate impairment charges of $34,833, $21,640 and $4,262, respectively, on real estate assets classified in continuing operations. The Company has explored the possible disposition of some non-core properties, including retail, underperforming and multi-tenant properties and determined that the expected undiscounted cash flows based upon revised estimated holding periods of certain of these properties were below the current carrying values. Accordingly, the Company reduced the carrying value of these properties to their estimated fair values. Properties impaired during 2014 and 2013 have an aggregate carrying value of $37,750 and are encumbered by an aggregate $61,763 of non-recourse mortgage debt as of December 31, 2014. During 2014, 2013 and 2012, the Company recognized $13,767, $12,920 and $5,707, respectively, of impairment charges in discontinued operations, relating to real estate assets that were ultimately disposed of below their carrying value.

Impairment of Real Estate Investments

The Company assesses on a regular basis whether there are any indicators that the carrying value of real estate assets may be impaired. Potential indicators may include an increase in vacancy at a property, tenant reduction in utilization of a property, tenant financial instability and the potential sale of the property in the near future. An asset is determined to be impaired if the asset's carrying value is in excess of its estimated fair value.

During 2014, 2013 and 2012, the Company recognized aggregate impairment charges of $34,833, $21,640 and $4,262, respectively, on real estate assets classified in continuing operations. The Company has explored the possible disposition of some non-core properties, including retail, underperforming and multi-tenant properties and determined that the expected undiscounted cash flows based upon revised estimated holding periods of certain of these properties were below the current carrying values. Accordingly, the Company reduced the carrying value of these properties to their estimated fair values. Properties impaired during 2014 and 2013 have an aggregate carrying value of $37,750 and are encumbered by an aggregate $61,763 of non-recourse mortgage debt as of December 31, 2014.

During 2014, 2013 and 2012, the Company recognized $13,767, $12,920 and $5,707, respectively, of impairment charges in discontinued operations, relating to real estate assets that were ultimately disposed of below their carrying value.