v3.26.3
Investor A C And Institutional [Member] Investment Objectives and Goals - Investor A C and Institutional - BlackRock California Municipal Opportunities Fund
May 31, 2026
Prospectus [Line Items]  
Risk/Return [Heading] Fund Overview Key Facts About BlackRock California Municipal Opportunities Fund
Objective [Heading] Investment Objective
Objective, Primary [Text Block]
The investment objective of BlackRock California Municipal Opportunities Fund (the “California Fund” or the “Fund”) is to provide shareholders with income exempt from Federal and California income taxes.