Equity and Capital - Accumulated Other Comprehensive Income (Loss) (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
Accumulated Other Comprehensive Income Loss [Line Items]
Document Fiscal Year Focus			2014
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (2,217)	$ (2,366)	$ (6,966)	$ (7,098)
Loss on Settlement of Derivative Instruments [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance			(52,542)	(61,991)
Net gain (loss) on cash flow derivative instruments	0	0	0	0
Amounts reclassified from other comprehensive income			6,628	7,086
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax			0	0
Current period other comprehensive income, net			6,628	7,086
Ending balance	(45,914)	(54,905)	(45,914)	(54,905)
Fair Value of Derivative Instruments [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance			35,138	4,276
Net gain (loss) on cash flow derivative instruments	(28,326)	22,187	(28,326)	22,187
Amounts reclassified from other comprehensive income			338	12
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax			0	0
Current period other comprehensive income, net			(27,988)	22,199
Ending balance	7,150	26,475	7,150	26,475
Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance			0	0
Net gain (loss) on cash flow derivative instruments	0	0	0	0
Amounts reclassified from other comprehensive income			0	0
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax			4,801	0
Current period other comprehensive income, net			4,801	0
Ending balance	4,801	0	4,801	0
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance			(17,404)	(57,715)
Net gain (loss) on cash flow derivative instruments	(28,326)	22,187	(28,326)	22,187
Amounts reclassified from other comprehensive income			6,966	7,098
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax			4,801	0
Current period other comprehensive income, net			(16,559)	29,285
Ending balance	(33,963)	(28,430)	(33,963)	(28,430)
Partnership Interest [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance			(17,404)
Current period other comprehensive income, net	2,504	2,896	(16,696)	29,348
Ending balance	(33,963)		(33,963)
Partnership Interest [Member] | General Partner [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Current period other comprehensive income, net			0	0
Partnership Interest [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Current period other comprehensive income, net			$ (16,559)	$ 29,285