Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Parenthetical) (Detail)	9 Months Ended
Sep. 30, 2016
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Redeemable shares, settlement period	3 days

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration