v3.25.3
Form N-1A Cover
Oct. 16, 2025
Prospectus [Line Items]  
Document Type 497
Amendment Flag false
Registrant Name T. Rowe Price QM U.S. Bond Index Fund, Inc.
Entity Central Index Key 0001120924
Entity Investment Company Type N-1A
Document Period End Date Oct. 16, 2025
Prospectus Date Jan. 01, 2025