Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Amounts attributable to Fluor Corporation:
Net earnings (loss) from continuing operations	$ (171,104)	$ (68,090)
Net earnings (loss) from discontinued operations	(94,855)	(814)
Net earnings (loss) attributable to Fluor Corporation	$ (265,959)	$ (68,904)
Basic EPS attributable to Fluor Corporation:
Weighted average common shares outstanding (shares)	140,262	139,776
Earnings (loss) from continuing operations (in dollars per share)	$ (1.22)	$ (0.49)
Earnings (loss) from discontinued operations, net of taxes (in dollars per share)	(0.68)	0
Net earnings (in dollars per share)	$ (1.90)	$ (0.49)
Diluted EPS attributable to Fluor Corporation:
Weighted average common shares outstanding (shares)	140,262	139,776
Diluted effect:
Employee stock options, restricted stock units and shares and Value Driver Incentive units (in shares)	0	0
Weighted average diluted shares outstanding (in shares)	140,262	139,776
Earnings (loss) from continuing operations (in dollars per share)	$ (1.22)	$ (0.49)
Earnings, (loss) from discontinued operations, net of taxes (in dollars per share)	(0.68)	0
Net earnings (in dollars per share)	$ (1.90)	$ (0.49)
Anti-dilutive securities not included above (in shares)	5,545	4,776
Employee stock options, restricted stock units and shares, and Value Driver Incentive units
Diluted effect:
Anti-dilutive securities not included above (in shares)	438	740