v3.25.4
N-2
6 Months Ended
Dec. 31, 2025
Cover [Abstract]  
Entity Central Index Key 0001870833
Amendment Flag false
Entity Inv Company Type N-2
Document Type N-CSRS
Entity Registrant Name RiverNorth Managed Duration Municipal Income Fund II, Inc.
Capital Stock, Long-Term Debt, and Other Securities [Abstract]  
Document Period End Date Dec. 31, 2025