Investments in and Advances to Joint Ventures - Revenues Earned By the Company from Unconsolidated Joint Ventures (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue from contracts:
Total revenue from contracts with customers	$ 11,945	$ 14,394	$ 42,928	$ 28,437
Other:
Interest income	4,200	4,800	12,600	14,600
Other	800	700	2,300	1,900
Total fee and other income	10,900	11,000	33,400	36,100
Asset and Property Management Fees [Member]
Revenue from contracts:
Total revenue from contracts with customers	9,751	10,501	32,392	20,982
Unconsolidated Joint Ventures [Member]
Revenue from contracts:
Total revenue from contracts with customers	5,900	5,500	18,500	19,600
Unconsolidated Joint Ventures [Member] | Asset and Property Management Fees [Member]
Revenue from contracts:
Total revenue from contracts with customers	4,700	4,000	14,800	14,500
Unconsolidated Joint Ventures [Member] | Development Fees, Leasing Commissions and Other [Member]
Revenue from contracts:
Total revenue from contracts with customers	$ 1,200	$ 1,500	$ 3,700	$ 5,100