Basic and Diluted Earnings Per Share (“EPS”) Data (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share, Basic and Diluted [Abstract]
Net income attributable to CDI	$ (20,202)	$ 5,400	$ (19,889)	$ 11,864
Basic weighted-average shares	19,695	19,614	19,668	19,562
Dilutive effect of stock-based awards		185		203
Diluted weighted-average shares	19,695	19,799	19,668	19,765
Earnings per common share:
Basic (per share)	$ (1.03)	$ 0.28	$ (1.01)	$ 0.61
Diluted (per share)	$ (1.03)	$ 0.27	$ (1.01)	$ 0.60
Antidilutive securities excluded from computation of EPS	672	406	374	290