Investment in Office Properties - Business Combination, Pro Forma (Details) (Tower Place 200, Deerwood North and South, Lincoln Place, CityWestPlace and Felipe Plaza [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Tower Place 200, Deerwood North and South, Lincoln Place, CityWestPlace and Felipe Plaza [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenues	$ 394,918	$ 363,498
Net loss attributable to common stockholders	$ (16,890)	$ (60,235)
Basic net income attributable to common stockholders	$ (0.52)	$ (2.38)
Diluted net income attributable to common stockholders	$ (0.52)	$ (2.38)