Revenue Recognition - Schedule of Revenue From Contracts With Customers Included in Fee and Other Income on Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Total revenue from contracts with customers	$ 14,394	$ 6,499	$ 28,437	$ 23,051
Other fee income:
Ancillary and other property income	2,384	4,444	11,607	13,535
Lease termination fees	99	9,380	3,316	10,188
Other	724	792	1,987	2,466
Total fee and other income	17,601	21,115	45,347	49,240
Asset and Property Management Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue from contracts with customers	10,501	4,660	20,982	16,851
Leasing Commissions [Member]
Disaggregation Of Revenue [Line Items]
Total revenue from contracts with customers	1,818	1,521	4,752	4,849
Development Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue from contracts with customers	393	318	1,021	1,351
Disposition Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue from contracts with customers	1,622	0	1,622	0
Credit Facility Guaranty Fee [Member]
Disaggregation Of Revenue [Line Items]
Total revenue from contracts with customers	$ 60	$ 0	$ 60	$ 0