v3.26.3
Investor A C Institutional And Class R [Member] Investment Objectives and Goals - Investor A, C, Institutional and Class R - BlackRock International Fund
May 31, 2026
Prospectus [Line Items]  
Risk/Return [Heading] Fund Overview Key Facts About BlackRock International Fund
Objective [Heading] Investment Objective
Objective, Primary [Text Block]
The investment objective of BlackRock International Fund (the “Fund”), a series of BlackRock Series, Inc. (the Corporation), is to seek long-term capital growth through investments primarily in a diversified portfolio of equity securities of companies located outside the United States.