Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income including noncontrolling interests		$ 64,597	$ 51,557	$ 173,995	$ 141,266
Other comprehensive income, net of tax:
Foreign currency translation adjustments		(39)	(255)	(730)	(1,056)
Post retirement plans, amortization of actuarial loss included in net income	[1]	640	440	1,874	1,393
Other comprehensive income		601	185	1,144	337
Comprehensive income		65,198	51,742	175,139	141,603
Less: Comprehensive income attributable to noncontrolling interests		0	(26)	0	(7)
Comprehensive income attributable to EMCOR Group, Inc.		$ 65,198	$ 51,716	$ 175,139	$ 141,596

[1] Net of tax of $0.2 million and $0.1 million for the three months ended September 30, 2017 and 2016, respectively, and net of tax of $0.5 million and $0.4 million for the nine months ended September 30, 2017 and 2016, respectively.