Discontinued Operations - Financial Information of Discontinued Operations (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
May 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net earnings (loss) from Disc Ops		$ 0	$ (32)	$ 0	$ (33)
Net earnings (loss) from Disc Ops attributable to Fluor		$ 0	(32)	$ 0	(33)
Discontinued Operations \| AMECO
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue			13		29
Cost of revenue			(21)		(37)
Gross Profit			(8)		(8)
G&A			0		0
Impairment expense			0		0
Loss on sale of AMECO North America	$ (27)		(25)		(25)
Foreign currency gain (loss)			0		0
Operating profit			(33)		(33)
Interest (expense) income, net			0		0
Earnings (loss) before taxes from Disc Ops			(33)		(33)
Income tax (expense) benefit			1		0
Net earnings (loss) from Disc Ops			(32)		(33)
Less: Net earnings (loss) from Disc Ops attributable to NCI			0		0
Net earnings (loss) from Disc Ops attributable to Fluor			$ (32)		$ (33)

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