Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Oct. 27, 2021
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-34726
Entity Registrant Name	LYONDELLBASELL INDUSTRIES N.V.
Entity Incorporation, State or Country Code	P7
Entity Tax Identification Number	98-0646235
Title of 12(b) Security	Ordinary Shares, €0.04 Par Value
Trading Symbol	LYB
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
Entity Common Stock, Shares Outstanding		332,783,944
Entity Central Index Key	0001489393
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Addresses [Line Items]
Entity Address, Address Line One	1221 McKinney St.,
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Houston,
Entity Address, State or Province	TX
Entity Address, Country	US
Entity Address, Postal Zip Code	77010
City Area Code	(713)
Local Phone Number	309-7200
United Kingdom [Member]
Entity Addresses [Line Items]
Entity Address, Address Line One	4th Floor, One Vine Street
Entity Address, City or Town	London
Entity Address, Country	GB
Entity Address, Postal Zip Code	W1J0AH
Country Region	+44 (0)
City Area Code	207
Local Phone Number	220 2600
Netherlands [Member]
Entity Addresses [Line Items]
Entity Address, Address Line One	Delftseplein 27E
Entity Address, City or Town	Rotterdam
Entity Address, Country	NL
Entity Address, Postal Zip Code	3013AA
Country Region	+31 (0)
City Area Code	10
Local Phone Number	2755 500