Income (Loss) Per Share - Computation of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator – Basic and Diluted:
Net (loss) income from continuing operations	$ 57	$ 902	$ (4)	$ 40	$ (5)	$ (12)	$ (55)	$ (30)	$ 995	$ (102)	$ 30
Less: Net income from continuing operations attributable to noncontrolling interest									26	12	37
Undistributed net income (loss) from continuing operations attributable to Tronox Holdings plc									969	(114)	(7)
Net income from discontinued operations available to ordinary shares									0	5	0
Net income (loss) available to ordinary shares									$ 969	$ (109)	$ (7)
Denominator – Basic and Diluted:
Weighted-average ordinary shares (thousands) (in shares)									143,355	139,859	122,881
Weighted average shares outstanding, diluted (in thousands) (in shares)									144,906	139,859	122,881
Net income (loss) per Ordinary Share:
Net income (loss) per share, basic (in dollars per share)	$ 0.31	$ 6.24	$ (0.03)	$ 0.23					$ 6.76	$ (0.81)	$ (0.06)
Basic net (loss) income from discontinued operations per ordinary share (in dollars per share)									0	0.03	0
Net income (loss) per share, basic (in dollars per share)									6.76	(0.78)	(0.06)
Diluted net loss from continuing operations per ordinary share (in dollars per share)	$ 0.31	$ 6.18	$ (0.03)	$ 0.22					6.69	(0.81)	(0.06)
Diluted net (loss) income from discontinued operations per ordinary share (in dollars per share)									0	0.03	0
Net income (loss) per share, diluted (in dollars per share)									$ 6.69	$ (0.78)	$ (0.06)