| Cover | Dec. 12, 2024 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Dec. 12, 2024 |
| Current Fiscal Year End Date | --12-31 |
| Entity File Number | 001-42435 |
| Entity Registrant Name | Roman DBDR Acquisition Corp. II |
| Entity Central Index Key | 0002032528 |
| Entity Tax Identification Number | 00-0000000 |
| Entity Incorporation, State or Country Code | E9 |
| Entity Address, Address Line One | 9858 Clint Moore Road, Suite 205 |
| Entity Address, City or Town | Boca Raton |
| Entity Address, State or Province | FL |
| Entity Address, Postal Zip Code | 33496 |
| City Area Code | 650 |
| Local Phone Number | 618-2524 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Units, each consisting of one Class A ordinary share and one-half of one redeemable warrant [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Units, each consisting of one Class A ordinary share and one-half of one redeemable warrant |
| Trading Symbol | DRDBU |
| Security Exchange Name | NASDAQ |
| Common Class A [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Class A ordinary shares, par value $0.0001 per share |
| Trading Symbol | DRDB |
| Security Exchange Name | NASDAQ |
| Warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 per share [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 per share |
| Trading Symbol | DRDBW |
| Security Exchange Name | NASDAQ |
