Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Document Fiscal Year Focus	2018
Other comprehensive income:
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	$ 0	$ 0	$ (20,945)
Parent Company [Member]
Net income	252,325	178,980	166,992
Other comprehensive income:
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	402	1,151	(10,332)
Reclassification adjustment of derivative instruments included in net income	5,342	11,103	51,139
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax	(95)	(8)	24
Other comprehensive income	5,649	12,246	40,831
Comprehensive income	257,974	191,226	207,823
Less: comprehensive income attributable to noncontrolling interests:
Net income attributable to noncontrolling interests	3,198	2,903	2,070
Other Comprehensive (Income) Loss, Net of Tax, Portion Attributable to Noncontrolling Interest	299	189	484
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	3,497	3,092	2,554
Comprehensive income attributable to the Company	254,477	188,134	205,269
Partnership Interest [Member]
Net income	252,325	178,980	166,992
Other comprehensive income:
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	402	1,151	(10,332)
Reclassification adjustment of derivative instruments included in net income	5,342	11,103	51,139
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax	(95)	(8)	24
Other comprehensive income	5,649	12,246	40,831
Comprehensive income	257,974	191,226	207,823
Less: comprehensive income attributable to noncontrolling interests:
Net income attributable to noncontrolling interests	2,673	2,515	1,813
Other Comprehensive (Income) Loss, Net of Tax, Portion Attributable to Noncontrolling Interest	288	168	426
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	2,961	2,683	2,239
Comprehensive income attributable to the Company	$ 255,013	$ 188,543	$ 205,584