Reportable Segments - (Reconciliation of Net Income to Net Operating Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Net Operating Income	$ 117,132	$ 97,417	$ 244,914	$ 185,148
Net operating income from unconsolidated joint ventures	(4,193)	(9,379)	(10,228)	(17,252)
Total Revenues	179,915	142,020	373,813	274,753
Reimbursed expenses	(322)	(1,047)	(843)	(1,979)
General and administrative expenses	(8,543)	(8,374)	(14,195)	(19,834)
Interest expense	(13,993)	(12,059)	(29,897)	(22,879)
Depreciation and amortization	(72,868)	(50,904)	(144,482)	(96,765)
Transaction costs	(63)	(49,827)	(428)	(49,830)
Other expenses	(552)	(624)	(1,118)	(804)
Income from unconsolidated joint ventures	1,715	3,634	5,140	6,538
Gain (loss) on sales of investments in unconsolidated joint ventures	(231)	0	45,999	0
Gain (loss) on investment property transactions	(201)	1,304	90,715	14,415
Net income (loss)	23,236	(22,582)	198,545	13,423
Fee income
Segment Reporting Information [Line Items]
Total Revenues	4,690	7,076	9,422	15,804
Termination fee income
Segment Reporting Information [Line Items]
Total Revenues	539	190	3,383	710
Other
Segment Reporting Information [Line Items]
Total Revenues	$ 126	$ 11	$ 163	$ 151