Comprehensive Income (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Changes in AOCI balances by component (after-tax) attributable to Fluor Corporation
Accumulated Other Comprehensive Income (Loss), Net, balance at the beginning of the period	$ (302,673)		$ (257,850)
Other comprehensive income (loss) before reclassifications	22,600		(26,766)
Amounts reclassified from AOCI	3,592		8,135
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	26,192	26,383	(18,631)	35,300
Accumulated Other Comprehensive Income (Loss), Net, balance at the end of the period	(276,481)		(276,481)
Foreign Currency Translation
Changes in AOCI balances by component (after-tax) attributable to Fluor Corporation
Accumulated Other Comprehensive Income (Loss), Net, balance at the beginning of the period	(10,902)		45,899
Other comprehensive income (loss) before reclassifications	26,471		(30,330)
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	26,471		(30,330)
Accumulated Other Comprehensive Income (Loss), Net, balance at the end of the period	15,569		15,569
Ownership Share of Equity Method Investees' Other Comprehensive Income (Loss)
Changes in AOCI balances by component (after-tax) attributable to Fluor Corporation
Accumulated Other Comprehensive Income (Loss), Net, balance at the beginning of the period	(36,928)		(43,019)
Other comprehensive income (loss) before reclassifications	2,262		8,353
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	2,262		8,353
Accumulated Other Comprehensive Income (Loss), Net, balance at the end of the period	(34,666)		(34,666)
Defined Benefit Pension and Postretirement Plans
Changes in AOCI balances by component (after-tax) attributable to Fluor Corporation
Accumulated Other Comprehensive Income (Loss), Net, balance at the beginning of the period	(243,899)		(252,724)
Other comprehensive income (loss) before reclassifications	(6,057)		(1,261)
Amounts reclassified from AOCI	2,012		6,041
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	(4,045)		4,780
Accumulated Other Comprehensive Income (Loss), Net, balance at the end of the period	(247,944)		(247,944)
Unrealized Gain (Loss) on Derivative Contracts
Changes in AOCI balances by component (after-tax) attributable to Fluor Corporation
Accumulated Other Comprehensive Income (Loss), Net, balance at the beginning of the period	(10,801)		(8,960)
Other comprehensive income (loss) before reclassifications	(443)		(2,883)
Amounts reclassified from AOCI	1,582		2,181
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	1,139		(702)
Accumulated Other Comprehensive Income (Loss), Net, balance at the end of the period	(9,662)		(9,662)
Unrealized Gain (Loss) on Available-for-Sale Securities
Changes in AOCI balances by component (after-tax) attributable to Fluor Corporation
Accumulated Other Comprehensive Income (Loss), Net, balance at the beginning of the period	(143)		954
Other comprehensive income (loss) before reclassifications	367		(645)
Amounts reclassified from AOCI	(2)		(87)
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	365		(732)
Accumulated Other Comprehensive Income (Loss), Net, balance at the end of the period	$ 222		$ 222