Discontinued Operations and Assets Held for Sale (Table Illustration of Discontinued Operations in Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Discontinued Operations
Revenues	$ 49	$ 29,331	$ 32,164	$ 59,403
Operating Expenses	(13)	(11,101)	(12,399)	(23,504)
Depreciation and amortization, discontinued operations	0	(9,141)	(3,517)	(19,107)
Operating Income (Loss)	36	9,089	16,248	16,792
Interest Expense	0	(3,618)	(6,053)	(7,399)
Income (loss) before gain on sales	36	5,471	10,195	9,393
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	399,390	8,322	427,924	31,996
Discontinued Operation, Tax Effect of Discontinued Operation	(3,220)	(546)	(3,220)	(3,523)
Income (loss) from discontinued operations	396,170	7,776	424,704	28,473
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	$ 399,354	$ 2,851	417,729	22,603
Payments For Second Generation Tenant Improvements Leasing Costs And Building Improvements			30,871	44,367
Discontinued Operations [Member]
Discontinued Operations
Payments For Second Generation Tenant Improvements Leasing Costs And Building Improvements			$ 7,400	$ 9,900