Services [Member] Expense Example - Services - BlackRock Pennsylvania Municipal Bond Fund - Service Shares	May 31, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 96
Expense Example, with Redemption, 3 Years	330
Expense Example, with Redemption, 5 Years	582
Expense Example, with Redemption, 10 Years	$ 1,305

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