Noncontrolling Interests (Redeemable Preferred Units) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning Balance			$ 51,312
Net Income	75	1,082	1,014	3,385
Redemption of redeemable preferred units (Series Four Preferred Units)			15,984	43,070
Ending Balance	2,022		2,022
Redeemable Preferred Units [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning Balance			51,312	110,876
Net Income			1,014	3,385
Distributions			(1,014)	(3,385)
Conversion of redeemable preferred units (Series Two Preferred Units) to common units			(33,306)
Redemption of redeemable preferred units (Series Four Preferred Units)			(15,984)	(43,070)
Ending Balance	$ 2,022	$ 67,806	$ 2,022	$ 67,806