S000004357 [Member] Expense Example - iShares 1-3 Year Treasury Bond ETF - iShares 1-3 Year Treasury Bond ETF	Feb. 28, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 15
Expense Example, with Redemption, 3 Years	48
Expense Example, with Redemption, 5 Years	85
Expense Example, with Redemption, 10 Years	$ 192

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