Subsequent Events/Other (Details) (USD $)	9 Months Ended		1 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Nov. 06, 2014 Subsequent Event [Member]	Oct. 31, 2014 Subsequent Event [Member]
Subsequent Event [Line Items]
Disposed Properties	4		4
Disposed Units	1,317		1,424
Proceeds From Sale Of Property	$ 227,602,000		$ 199,500,000
Notional Amount Of Hedge Instruments				100,000,000
Business Combination, Acquisition Related Costs	300,000	200,000
Noncash Project Abandonment Costs	2,067,000	3,969,000
Other Expenses	2,400,000	4,200,000
Litigation Settlement, Amount	$ 2,800,000