Cover - shares	6 Months Ended
	Jun. 30, 2020	Jul. 24, 2020
Class of Stock [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	001-38081
Entity Registrant Name	Liberty Oilfield Services Inc.
Entity Incorporation, State or Country Code	DE
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
Title of 12(b) Security	Class A Common Stock, par value $0.01
Trading Symbol	LBRT
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2020
Amendment Flag	false
Entity Central Index Key	0001694028
Current Fiscal Year End Date	--12-31
Shares of Class A Common Stock
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		84,853,162
Shares of Class B Common Stock
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		28,080,525