Debt, Formation of LYB International Finance B.V., LYB International Finance II B.V. and LYB International Finance III, LLC (Details)	6 Months Ended
	Jun. 30, 2020
Formation of 100% owned finance subsidiaries [Abstract]
LYB International Finance B.V., LYB International Finance II B.V. and LYB International Finance III, LLC business activities and description	LYB International Finance B.V., LYB International Finance II B.V. and LYB International Finance III, LLC are 100% owned finance subsidiaries of LyondellBasell Industries N.V., as defined in Rule 3-10(b) of Regulation S-X. Any debt securities issued by LYB International Finance B.V., LYB International Finance II B.V. and LYB International Finance III, LLC are fully and unconditionally guaranteed by LyondellBasell Industries N.V.