Consolidated Statement of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings (Loss) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	CECO	Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2013	$ 170,406	$ 257	$ 159,566	$ 11,911	$ (972)	$ (356)	$ 170,406
Beginning Balance, Shares at Dec. 31, 2013		25,725,000				(138,000)
Net (loss) income	13,077			13,077			13,077
Common stock dividends	(5,937)			(5,937)			(5,937)
Exercise of stock options and dividend reinvestment issuances	$ 1,383	$ 3	1,380				1,383
Exercise of stock options and dividend reinvestment issuances, Shares	239,000	247,000
Excess tax benefit from stock options exercised	$ 923		923				923
Share based compensation earned	1,659		1,659				1,659
Share based compensation earned, Shares		7,000
Stock repurchase and retirement	(973)	$ (1)	(972)				(973)
Stock repurchase and retirement, Shares		(61,500)
Stock issued for acquisitions	6,335	$ 5	6,330				6,335
Stock issued for acquisitions, Shares		488,000
Minimum pension/postretirement liability adjustment	(4,052)				(4,052)		(4,052)
Translation loss	(1,597)				(1,597)		(1,597)
Ending Balance at Dec. 31, 2014	181,224	$ 264	168,886	19,051	(6,621)	$ (356)	181,224
Ending Balance, Shares at Dec. 31, 2014		26,405,000				(138,000)
Translation (loss) gain, beginning balance at Dec. 31, 2013	(146)
Translation (loss) gain, ending balance at Dec. 31, 2014	(1,743)
Minimum pension/post retirement liability adjustment beginning balance at Dec. 31, 2013	(826)
Minimum pension/post retirement liability adjustment, ending balance at Dec. 31, 2014	(4,878)
Accumulated other comprehensive loss, beginning balance at Dec. 31, 2013	(972)
Accumulated other comprehensive loss, activity	(5,649)
Accumulated other comprehensive loss, ending balance at Dec. 31, 2014	(6,621)
Net (loss) income	(5,734)			(5,602)			(5,602)	$ (132)
Common stock dividends	(7,977)			(7,977)			(7,977)
Exercise of stock options and dividend reinvestment issuances	$ 205		205				205
Exercise of stock options and dividend reinvestment issuances, Shares	30,000	36,000
Excess tax benefit from stock options exercised	$ 44		44				44
Share based compensation earned	2,070		2,070				2,070
Share based compensation earned, Shares		13,000
Stock repurchase and retirement, Shares		0
Stock issued for acquisitions	72,145	$ 76	72,069				72,145
Stock issued for acquisitions, Shares		7,602,000
Fair value of noncontrolling interest acquired	6,000							6,000
Minimum pension/postretirement liability adjustment	(292)				(292)		(292)
Translation loss	(2,664)				(2,664)		(2,664)
Ending Balance at Dec. 31, 2015	245,021	$ 340	243,274	5,472	(9,577)	$ (356)	239,153	5,868
Ending Balance, Shares at Dec. 31, 2015		26,405,000				(138,000)
Translation (loss) gain, ending balance at Dec. 31, 2015	(4,407)
Minimum pension/post retirement liability adjustment, ending balance at Dec. 31, 2015	(5,170)
Accumulated other comprehensive loss, activity	(2,956)
Accumulated other comprehensive loss, ending balance at Dec. 31, 2015	(9,577)
Net (loss) income	(38,254)			(38,218)			(38,218)	(36)
Common stock dividends	(8,995)			(8,995)			(8,995)
Exercise of stock options and dividend reinvestment issuances	$ 1,515	$ 2	1,513				1,515
Exercise of stock options and dividend reinvestment issuances, Shares	195,000	215,000
Excess tax benefit from stock options exercised	$ 137		137				137
Restricted stock units issued	(9)		(9)				(9)
Restricted stock units issued, Shares		17,000
Share based compensation earned	2,458	$ 1	2,457				2,458
Share based compensation earned, Shares		27,000
Issuance of shares for cashless warrant exercise		$ 1	(1)
Issuance of shares for cashless warrant exercise, Shares		90,000
Stock repurchase and retirement	(1,238)	$ (1)	(1,237)				(1,238)
Stock repurchase and retirement, Shares		(105,000)
Noncontrolling interest acquisitions, net of purchase accounting adjustments	(7,088)		(1,256)				(1,256)	$ (5,832)
Minimum pension/postretirement liability adjustment	87				87		87
Translation loss	(3,864)				(3,864)		(3,864)
Ending Balance at Dec. 31, 2016	190,082	$ 343	$ 244,878	$ (41,741)	(13,042)	$ (356)	190,082
Ending Balance, Shares at Dec. 31, 2016		34,300,000				(138,000)
Interest rate swap	312				$ 312		$ 312
Translation (loss) gain, ending balance at Dec. 31, 2016	(8,271)
Minimum pension/post retirement liability adjustment, ending balance at Dec. 31, 2016	(5,083)
Accumulated other comprehensive loss, activity	(3,465)
Accumulated other comprehensive loss, ending balance at Dec. 31, 2016	(13,042)
Interest rate swap liability adjustment ending balance at Dec. 31, 2016	$ 312