Segment Information - Schedule of Reconciliation of Net Income Attributable to Parent (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Net income (loss) attributable to common shareholders	$ (36,780,000)	$ (3,040,000)	$ 6,145,000	$ 21,821,000
Depreciation and amortization expense	52,616,000	45,995,000	101,105,000	94,714,000
Corporate and other	13,216,000	11,559,000	26,392,000	23,873,000
Third-party real estate services	29,239,000	28,710,000	58,053,000	56,776,000
Share-based compensation related to Formation Transaction and special equity awards	8,858,000	9,523,000	18,299,000	20,654,000
Transaction and other costs	1,372,000	2,974,000	6,681,000	7,869,000
Interest expense	15,770,000	13,107,000	27,775,000	30,281,000
Loss on extinguishment of debt		1,889,000	33,000	1,889,000
Income tax expense (benefit)	(888,000)	51,000	(3,233,000)	(1,121,000)
Net income (loss) attributable to redeemable noncontrolling interests	(3,483,000)	(288,000)	1,767,000	3,099,000
Third-party real estate services, including reimbursements	27,167,000	29,487,000	56,883,000	57,178,000
Other revenue	1,516,000	2,114,000	3,146,000	3,755,000
Income (loss) from unconsolidated real estate ventures, net	(13,485,000)	(1,810,000)	(16,177,000)	1,791,000
Interest and other income, net	114,000	2,052,000	1,021,000	3,003,000
Gain on sale of real estate			59,477,000	39,033,000
Consolidated NOI	64,608,000	78,637,000	138,667,000	155,095,000
Parking
Segment Reporting Information [Line Items]
Revenue	$ 810,000	$ 6,700,000	$ 7,200,000	$ 13,100,000