Segment Information - Summary of Third-party Asset Management and Real Estate Services (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Third-party real estate services revenue, excluding reimbursements	$ 65,452	$ 59,684	$ 36,329
Reimbursement Revenue from Third Parties	55,434	39,015	26,907
Revenue from Contract with Customer, Including Reimbursements	120,886	98,699	63,236
Property management fees
Third-party real estate services revenue, excluding reimbursements	22,437	24,831	16,022
Asset management fees
Third-party real estate services revenue, excluding reimbursements	14,045	14,910	10,083
Leasing fees
Third-party real estate services revenue, excluding reimbursements	7,377	6,658	3,639
Development fees
Third-party real estate services revenue, excluding reimbursements	15,655	7,592	3,653
Construction management fees
Third-party real estate services revenue, excluding reimbursements	1,669	2,892	2,220
Other service revenue
Third-party real estate services revenue, excluding reimbursements	$ 4,269	$ 2,801	$ 712