Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Amounts attributable to Fluor Corporation:
Net earnings (loss) attributable to Fluor Corporation from Cont Ops	$ (26,934)	$ (397,430)	$ (198,038)	$ (465,520)
Net earnings (loss) from Disc Ops	1,944	(16,591)	(92,911)	(17,405)
Net earnings (loss)	$ (24,990)	$ (414,021)	$ (290,949)	$ (482,925)
Basic EPS attributable to Fluor Corporation:
Weighted average common shares outstanding (shares)	140,536	140,141	140,399	139,959
Earnings (loss) from continuing operations (in dollars per share)	$ (0.19)	$ (2.84)	$ (1.41)	$ (3.33)
Earnings (loss) from discontinued operations, net of taxes (in dollars per share)	0.01	(0.11)	(0.66)	(0.12)
Net earnings (in dollars per share)	$ (0.18)	$ (2.95)	$ (2.07)	$ (3.45)
Diluted EPS attributable to Fluor Corporation:
Weighted average common shares outstanding (shares)	140,536	140,141	140,399	139,959
Diluted effect:
Employee stock options, restricted stock units and shares and Value Driver Incentive units (in shares)	0	0	0	0
Weighted average diluted shares outstanding (in shares)	140,536	140,141	140,399	139,959
Earnings (loss) from continuing operations (in dollars per share)	$ (0.19)	$ (2.84)	$ (1.41)	$ (3.33)
Earnings, (loss) from discontinued operations, net of taxes (in dollars per share)	0.01	(0.11)	(0.66)	(0.12)
Net earnings (in dollars per share)	$ (0.18)	$ (2.95)	$ (2.07)	$ (3.45)
Anti-dilutive securities not included above (in shares)	384	526	411	633