Income Taxes (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Income Tax Expense (Benefit)	$ (134)	$ 2,590	$ 3,251
7.875% Series A
Class of Stock [Line Items]
Prior Year Distributions Carryforward as Current Year Distribution				$ 0.4261
8.00% Series B [Member]
Class of Stock [Line Items]
Prior Year Distributions Carryforward as Current Year Distribution				0.4328
6.50% Series C [Member]
Class of Stock [Line Items]
Prior Year Distributions Carryforward as Current Year Distribution				$ 0.3517
Common Shares [Member]
Class of Stock [Line Items]
Prior Year Distributions Carryforward as Current Year Distribution	$ 0.2866	$ 0.2164	$ 0.1692
Operating Partnership [Member]
Class of Stock [Line Items]
Income Tax Expense (Benefit)	$ 500	$ 900	$ 200