Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Other comprehensive income (loss), Before-Tax Amount:
Total other comprehensive income (loss), Before-Tax Amount	$ 41,005	$ 41,899	$ (32,051)	$ 56,892
Less: Other comprehensive loss attributable to noncontrolling interests, Before-Tax Amount	(403)	(250)	(350)	(587)
Other comprehensive income (loss) attributable to Fluor Corporation, Before-Tax Amount	41,408	42,149	(31,701)	57,479
Other comprehensive income (loss), Tax Benefit (Expense):
Total other comprehensive income (loss), Tax Benefit (Expense)	(15,216)	(15,766)	13,070	(22,179)
Other comprehensive income (loss) attributable to Fluor Corporation, Tax Benefit (Expense)	(15,216)	(15,766)	13,070	(22,179)
Other comprehensive income (loss), Net-of-Tax:
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	25,789	26,133	(18,981)	34,713
Less: Other comprehensive loss attributable to noncontrolling interests, Net-of-Tax Amount	(403)	(250)	(350)	(587)
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	26,192	26,383	(18,631)	35,300
Foreign currency translation adjustment
Other comprehensive income (loss), Before-Tax Amount:
Total other comprehensive income (loss), Before-Tax Amount	42,074	38,768	(48,753)	43,922
Other comprehensive income (loss), Tax Benefit (Expense):
Total other comprehensive income (loss), Tax Benefit (Expense)	(15,882)	(14,600)	18,198	(16,506)
Other comprehensive income (loss), Net-of-Tax:
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	26,192	24,168	(30,555)	27,416
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	26,471		(30,330)
Ownership share of equity method investees' other comprehensive income
Other comprehensive income (loss), Before-Tax Amount:
Total other comprehensive income (loss), Before-Tax Amount	3,118	165	11,471	(1,138)
Other comprehensive income (loss), Tax Benefit (Expense):
Total other comprehensive income (loss), Tax Benefit (Expense)	(856)	(32)	(3,118)	(218)
Other comprehensive income (loss), Net-of-Tax:
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	2,262	133	8,353	(1,356)
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	2,262		8,353
Defined benefit pension and postretirement plan adjustments
Other comprehensive income (loss), Before-Tax Amount:
Total other comprehensive income (loss), Before-Tax Amount	(6,472)	1,643	7,648	10,187
Other comprehensive income (loss), Tax Benefit (Expense):
Total other comprehensive income (loss), Tax Benefit (Expense)	2,427	(616)	(2,868)	(3,820)
Other comprehensive income (loss), Net-of-Tax:
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	(4,045)	1,027	4,780	6,367
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	(4,045)		4,780
Unrealized gain (loss) on derivative contracts
Other comprehensive income (loss), Before-Tax Amount:
Total other comprehensive income (loss), Before-Tax Amount	1,700	693	(1,247)	3,465
Other comprehensive income (loss), Tax Benefit (Expense):
Total other comprehensive income (loss), Tax Benefit (Expense)	(685)	(281)	420	(1,464)
Other comprehensive income (loss), Net-of-Tax:
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	1,015	412	(827)	2,001
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	1,139		(702)
Unrealized gain (loss) on debt securities
Other comprehensive income (loss), Before-Tax Amount:
Total other comprehensive income (loss), Before-Tax Amount	585	630	(1,170)	456
Other comprehensive income (loss), Tax Benefit (Expense):
Total other comprehensive income (loss), Tax Benefit (Expense)	(220)	(237)	438	(171)
Other comprehensive income (loss), Net-of-Tax:
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	365	393	(732)	285
Other comprehensive income (loss) attributable to Fluor Corporation, Net-of-Tax Amount	$ 365		$ (732)