Dispositions (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Dispositions [Abstract]
Real Estate, Net	$ 29,517		$ 29,561
Other Assets	6,997		7,459
Assets related to discontinued operations	36,514		37,020
Other Liabilities	12,902		12,470
Liabilities related to discontinued operations	12,902		$ 12,470
Income from discontinued operations:
Total revenues	1,182	$ 20,296
Total expenses	466	13,373
Income from discontinued operations before gain on sale of real estate	716	6,923
Transaction related costs (primarily UE Spin off)	0	(22,645)
Net gain on sale of lease position in Geary Street, CA	0	21,376
Net gains on sale of real estate	0	10,867
Impairment losses	0	(256)
Pretax income from discontinued operations	716	16,265
Income tax expense	0	(86)
Income from Discontinued Operations	716	16,179
Cash flows related to discontinued Operations:
Cash flows from operating activities, discontinued operations	1,654	(36,672)
Cash flows from investing activities, discontinued operations	$ 0	$ 310,069