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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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Partnerships and Joint Ventures - Narrative (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020 USD ($)	Dec. 31, 2021 USD ($) investment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Variable interest entity information
Asset impairments	$ 103,000		$ 0	$ 29,485
Number of joint ventures divested \| investment		3
Cooec Fluor Heavy Industries Co. Limited
Variable interest entity information
Future funding commitments		$ 26,000
Cooec Fluor Heavy Industries Co. Limited
Variable interest entity information
Asset impairments		$ 28,000	86,000	$ 257,000
Ownership interest (as a percent)		49.00%
Sacyr Fluor \| Discontinued Operations, Disposed of by Sale \| Urban Solutions
Variable interest entity information
Ownership interest (as a percent)		10.00%
Gain (loss) on sale of investments		$ 20,000
Sacyr Fluor \| Discontinued Operations, Disposed of by Sale \| Energy Solutions
Variable interest entity information
Ownership interest (as a percent)		50.00%
Gain (loss) on sale of investments		$ (11,000)
Infrastructure Joint Venture \| Discontinued Operations, Disposed of by Sale
Variable interest entity information
Gain (loss) on sale of investments		8,000
Variable Interest Entity, Not Primary Beneficiary \| Accounts and notes receivable, net
Variable interest entity information
Receivables related to work performed for unconsolidated partnerships and joint ventures		204,000	$ 207,000
Variable Interest Entity, Not Primary Beneficiary \| Accrued Liabilities
Variable interest entity information
Investments in loss position, included in other accrued liabilities		$ 240,000
Fluor Corporation \| Majority \| Partnership
Variable interest entity information
Entity's interest in partnership or joint venture (percent)		50.00%