Earnings Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share
Net income attributable to EMCOR Group, Inc. available to common stockholders	$ 28,809	$ 27,141	$ 53,403	$ 48,958
Weighted average shares outstanding used to compute basic earnings per common share	66,848,078	66,314,596	66,828,523	66,315,338
Effect of diluted securities - Share-based awards	1,743,692	1,656,971	1,758,141	1,619,545
Shares used to compute diluted earnings per common share	68,591,770	67,971,567	68,586,664	67,934,883
Net income attributable to EMCOR Group, Inc. available to common stockholders	$ 0.43	$ 0.41	$ 0.80	$ 0.74
Net income attributable to EMCOR Group, Inc. available to common stockholders	$ 0.42	$ 0.40	$ 0.78	$ 0.72
Antidilutive Securities Excluded from Computation of Earnings Per Share	200,000	301,347	220,096	311,347