Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Document Fiscal Year Focus			2015
Other comprehensive loss:
Effective portion of change in fair value of derivative instruments	$ 18,376	$ (11,153)	$ 4,494	$ (24,953)
Parent Company [Member]
Net income	(38,280)	(31,161)	(69,271)	(56,217)
Other comprehensive loss:
Amortization of loss on settled derivative instruments recognized in net income	2,107	2,165	4,215	4,532
Effective portion of change in fair value of derivative instruments	18,376	(11,153)	4,494	(24,953)
Less: reclassification adjustment for change in fair value of derivative instruments included in net income	143	153	285	305
Available-for-sale Securities, Gross Unrealized Gain	(30)	914	(30)	914
Other comprehensive income (loss)	20,596	(7,921)	8,964	(19,202)
Comprehensive income	58,876	23,240	78,235	37,015
Less: comprehensive income (loss) attributable to noncontrolling interests:
Net income attributable to noncontrolling interests	(534)	(413)	(1,087)	(814)
Other comprehensive income (loss) attributable to noncontrolling interests	119	(108)	15	(194)
Comprehensive income attributable to noncontrolling interests	653	305	1,102	620
Comprehensive income attributable to the Company	58,223	22,935	77,133	36,395
Partnership Interest [Member]
Net income	(38,280)	(31,161)	(69,271)	(56,217)
Other comprehensive loss:
Amortization of loss on settled derivative instruments recognized in net income	2,107	2,165	4,215	4,532
Effective portion of change in fair value of derivative instruments	18,376	(11,153)	4,494	(24,953)
Less: reclassification adjustment for change in fair value of derivative instruments included in net income	143	153	285	305
Available-for-sale Securities, Gross Unrealized Gain	(30)	914	(30)	914
Other comprehensive income (loss)	20,596	(7,921)	8,964	(19,202)
Comprehensive income	58,876	23,240	78,235	37,015
Less: comprehensive income (loss) attributable to noncontrolling interests:
Net income attributable to noncontrolling interests	(473)	(360)	(977)	(719)
Other comprehensive income (loss) attributable to noncontrolling interests	86	(92)	0	(160)
Comprehensive income attributable to noncontrolling interests	559	268	977	559
Comprehensive income attributable to the Company	$ 58,317	$ 22,972	$ 77,258	$ 36,456