Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2016	Mar. 18, 2016	Jul. 31, 2015
Document And Entity Information
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jan. 31, 2016
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Entity Current Reporting Status	Yes
Entity Registrant Name	KLX Inc.
Entity Central Index Key	0001617898
Current Fiscal Year End Date	--01-31
Entity Filer Category	Large Accelerated Filer
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Entity Common Stock, Shares Outstanding		52,786,474
Entity Public Float			$ 2,072