Investment in Real Estate - Fair Value Measurement on Non-Recurring Basis (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Impairment	$ (626)
Fair Value, Measurements, Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Operating Property Not Held for Sale	17,850
Fair Value, Measurements, Nonrecurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Operating Property Not Held for Sale	0
Fair Value, Measurements, Nonrecurring | Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Operating Property Not Held for Sale	0
Fair Value, Measurements, Nonrecurring | Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Operating Property Not Held for Sale	$ 17,850