Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2018	Mar. 11, 2019	Jun. 30, 2018
Document Information [Line Items]
Entity Registrant Name	TENNECO INC
Entity Central Index Key	0001024725
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	TEN
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 2.2
Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		57,126,127
Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		23,793,669