Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 25, 2015	Sep. 30, 2016	Sep. 25, 2015
Earnings Per Share
Period for aggregate contractual obligation				5 years
Numerator - basic and diluted:
Net (loss) income		$ (33,649)	$ 48,505	$ (164,115)	$ 79,116
Less: loss (income) attributable to noncontrolling interests		49,582	(9,060)	142,585	(12,423)
Net income attributable to CH2M		15,933	39,445	(21,530)	66,693
Less: accrued dividends attributable to preferred stockholders		3,891	2,501	10,067	2,556
Less: income allocated to preferred stockholders - basic		1,984	3,913		2,502
Net income (loss) available to common stockholders - basic and diluted		$ 10,058	$ 33,031	$ (31,597)	$ 61,635
Denominators:
Weighted-average common shares outstanding - basic		25,356,689	27,139,832	25,816,819	27,281,219
Dilutive effect of common stock equivalents (in shares)		32,000	59,000		16,000
Diluted adjusted weighted-average common shares outstanding, assuming conversion of common stock equivalents (in shares)		25,389,138	27,198,832	25,816,819	27,297,219
Basic net (loss) income per common share	[1]	$ 0.40	$ 1.22	$ (1.22)	$ 2.26
Diluted net (loss) income per common share	[1]	$ 0.40	$ 1.22	$ (1.22)	$ 2.26

[1] Represents net (loss) income attributable to CH2M less (i) income allocated to preferred stockholders of $1,984 for the three months ended September 30, 2016 and $3,913 and $2,502 for the three and nine months ended September 25, 2015, respectively, and (ii) accrued dividends attributable to preferred stockholders of $3,891 and $10,067 for the three and nine months ended September 30, 2016, respectively, and $2,501 and $2,556 for the three and nine months ended September 25, 2015, respectively