Organization and Basis of Presentation - Additional Information (Detail) ft² in Millions	3 Months Ended
	Mar. 31, 2017 ft² Property
Organization And Significant Accounting Policies [Line Items]
Outstanding common units of aggregate limited partnership interest owned percentage	80.50%
Wholly Owned Operating Properties [Member]
Organization And Significant Accounting Policies [Line Items]
Number of properties	44
Aggregate area of land | ft²	3.2
Wholly Owned Operating Properties [Member] | Government [Member]
Organization And Significant Accounting Policies [Line Items]
Number of properties	41
Wholly Owned Operating Properties [Member] | Private Tenants [Member]
Organization And Significant Accounting Policies [Line Items]
Number of properties	3
Wholly Owned Properties Under Development [Member]
Organization And Significant Accounting Policies [Line Items]
Number of properties	1
Aggregate area of land | ft²	0.1