The number of parties to the joint venture.

No definition available.

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=SL6759159-111685

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=flr_FundingCommitmentAdditionalInvestmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=flr_OffshoreOilEngineeringCompanyLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=flr_CooecFluorHeavyIndustriesCo.LimitedMember
Namespace Prefix:
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Partnerships and Joint Ventures - Joint Venture Investment Agreement (Details) $ in Millions	1 Months Ended	12 Months Ended
	Feb. 29, 2016 USD ($) company	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
COOEC Fluor Heavy Industries Co., Ltd.
Commitments
Cash investment in joint venture	$ 350	$ 26	$ 62
Ownership interest in joint venture (as a percent)	49.00%
COOEC Fluor Heavy Industries Co., Ltd. \| Funding commitment, additional investments
Commitments
Commitment amount		$ 52
Offshore Oil Engineering Co., Ltd. \| COOEC Fluor Heavy Industries Co., Ltd.
Commitments
Ownership interest in joint venture (as a percent)	51.00%
COOEC Fluor Heavy Industries Co., Ltd.
Commitments
Number of parties to joint venture \| company	2