Services [Member] Expense Example - Service - BlackRock New Jersey Municipal Bond Fund - Service Shares	May 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 80
Expense Example, with Redemption, 3 Years	294
Expense Example, with Redemption, 5 Years	527
Expense Example, with Redemption, 10 Years	$ 1,194

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