Non-Controlling Interests - Schedule of OP Units Exchanged for Shares of Common Stock (Detail) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Minority Interest [Line Items]
OP Units exchanged	8	37
Common Stock
Minority Interest [Line Items]
Shares of common stock received	8	37
Additional Paid-in Capital
Minority Interest [Line Items]
Value of shares/units exchanged	$ 684	$ 2,986

The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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Balance Type:	na
Period Type:	duration