S000075207 [Member] Expense Example - iShares U.S. Securitized Bond Index Fund - iShares U.S. Securitized Bond Index Fund	Oct. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 1
Expense Example, with Redemption, 3 Years	3
Expense Example, with Redemption, 5 Years	6
Expense Example, with Redemption, 10 Years	$ 13

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