Earnings Per Share (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share
Net earnings attributable to Fluor Corporation (in dollars)	$ 173,046,000	$ 144,583,000	$ 500,916,000	$ 460,655,000
Basic EPS:
Weighted average common shares outstanding (in shares)	162,940,000	166,660,000	162,715,000	167,925,000
Basic earnings per share (in dollars per share)	$ 1.06	$ 0.87	$ 3.08	$ 2.74
Diluted EPS:
Weighted average common shares outstanding (in shares)	162,940,000	166,660,000	162,715,000	167,925,000
Diluted effect:
Employee stock options and restricted stock units and shares (in shares)	1,490,000	964,000	1,218,000	1,004,000
Conversion equivalent of dilutive convertible debt (in shares)	415,000	344,000	391,000	342,000
Weighted average diluted shares outstanding (in shares)	164,845,000	167,968,000	164,324,000	169,271,000
Diluted earnings per share (in dollars per share)	$ 1.05	$ 0.86	$ 3.05	$ 2.72
Anti-dilutive securities not included above (in shares)	1,845,000	1,653,000	1,914,000	1,529,000
Common stock repurchased and cancelled, shares (in shares)		600,900		3,223,949
Common stock repurchased and cancelled, amount (in dollars)		$ 31,000,000		$ 164,000,000