Earnings Per Share (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Earnings Per Share
Net earnings attributable to Fluor Corporation (in dollars)	$ 166,458,000	$ 154,882,000
Basic EPS:
Weighted average common shares outstanding (in shares)	162,408,000	168,852,000
Basic earnings per share (in dollars per share)	$ 1.02	$ 0.92
Diluted EPS:
Weighted average common shares outstanding (in shares)	162,408,000	168,852,000
Diluted effect:
Employee stock options and restricted stock units and shares (in shares)	1,191,000	1,178,000
Conversion equivalent of dilutive convertible debt (in shares)	392,000	376,000
Weighted average diluted shares outstanding (in shares)	163,991,000	170,406,000
Diluted earnings per share (in dollars per share)	$ 1.02	$ 0.91
Anti-dilutive securities not included above (in shares)	1,382,000	1,216,000
Common stock repurchased and cancelled, shares (in shares)		450,000
Common stock repurchased and cancelled, amount (in dollars)		$ 27,000,000