S000080646 [Member] Expense Example - iShares Large Cap Deep Buffer ETF - iShares Large Cap Deep Buffer ETF	Jul. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 51
Expense Example, with Redemption, 3 Years	167
Expense Example, with Redemption, 5 Years	293
Expense Example, with Redemption, 10 Years	$ 662

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