Income Taxes - Additional Information (Detail)	3 Months Ended
Mar. 31, 2018
Minimum [Member]
Income Tax Contingency [Line Items]
Distribution of taxable income to qualify as REIT, percent	90.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Balance Type:	na
Period Type:	duration