Expense Example - BLACKROCK NATURAL RESOURCES TRUST	Apr. 30, 2025 USD ($)
Investor A Shares
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 637
Expense Example, with Redemption, 3 Years	874
Expense Example, with Redemption, 5 Years	1,130
Expense Example, with Redemption, 10 Years	1,860
Investor C Shares
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	291
Expense Example, with Redemption, 3 Years	591
Expense Example, with Redemption, 5 Years	1,016
Expense Example, with Redemption, 10 Years	2,013
Institutional Shares
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	93
Expense Example, with Redemption, 3 Years	290
Expense Example, with Redemption, 5 Years	504
Expense Example, with Redemption, 10 Years	$ 1,120

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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