Earnings (Loss) Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic (loss) earnings per common share
Net (loss) income attributable to XPO	$ (131)	$ 135	$ (108)	$ 182
Series A preferred stock dividends	(1)	0	(2)	(1)
Non-cash allocation of undistributed loss (earnings)	0	(13)	0	(16)
Net (loss) income attributable to common shares, basic	$ (132)	$ 122	$ (110)	$ 165
Basic weighted-average common shares (in shares)	91	92	92	100
Basic (loss) earnings per share (in dollars per share)	$ (1.45)	$ 1.32	$ (1.20)	$ 1.66
Diluted (loss) earnings per common share
Net (loss) income attributable to common shares, diluted	$ (132)	$ 122	$ (110)	$ 165
Basic weighted-average common shares (in shares)	91	92	92	100
Dilutive effect of non-participating stock-based awards and equity forward (in shares)	0	10	0	10
Diluted weighted-average common shares (in shares)	91	102	92	110
Diluted (loss) earnings per share (in dollars per share)	$ (1.45)	$ 1.19	$ (1.20)	$ 1.51
Potential common shares excluded (in shares)	20	10	21	10