Quarterly report pursuant to Section 13 or 15(d)

Non-Controlling Interest - Additional Information (Detail)

v3.8.0.1
Non-Controlling Interest - Additional Information (Detail) - USD ($)
9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Noncontrolling Interest [Line Items]    
Exchange of operating partnership units to common stock 0 0
Payment in cash for redemption of operating partnership units $ 0  
Maximum [Member]    
Noncontrolling Interest [Line Items]    
Outstanding OP units held by outside limited partners 1.00%