Fair Value Measurements - Additional Information (Detail) - Property	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Number of investment properties carried at fair value	0	14
Number of investment properties Held for Sale		6

Number Of Real Estate Investment Properties Carried At Fair Value

No definition available.

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Data Type:	xbrli:integerItemType
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Period Type:	instant