| Document and Entity Information | Jun. 07, 2021 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001694028 |
| Document Type | 8-K |
| Document Period End Date | Jun. 7, 2021 |
| Entity Registrant Name | LIBERTY OILFIELD SERVICES INC. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-38081 |
| Entity Tax Identification Number | 81-4891595 |
| Entity Address, Address Line One | 950 17th Street |
| Entity Address, Address Line Two | Suite 2400 |
| Entity Address, City or Town | Denver |
| Entity Address, State or Province | CO |
| Entity Address, Postal Zip Code | 80202 |
| City Area Code | (303) |
| Local Phone Number | 515-2800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Class A Common Stock, par value $0.01 |
| Trading Symbol | LBRT |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
