Expense Example - Institutional - BlackRock China A Opportunities Fund - Institutional	Feb. 26, 2021 USD ($)
Expense Example:
Expense Example, with Redemption, 1 Year	$ 101
Expense Example, with Redemption, 3 Years	595
Expense Example, with Redemption, 5 Years	1,115
Expense Example, with Redemption, 10 Years	$ 2,544

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The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section 3
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Form
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-Chapter A
-Section 3
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-Subparagraph 2

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