Basic and Diluted Earnings Per Share (“EPS”) Data (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share, Basic and Diluted [Abstract]
Net income attributable to CDI	$ (7,484)	$ (157)	$ (12,301)	$ 313
Basic weighted-average shares	19,174	19,675	19,427	19,655
Dilutive effect of stock-based awards	0	0	0	191
Diluted weighted-average shares	19,174	19,675	19,427	19,846
Earnings per common share:
Basic (per share)	$ (0.39)	$ (0.01)	$ (0.63)	$ 0.02
Diluted (per share)	$ (0.39)	$ (0.01)	$ (0.63)	$ 0.02
Antidilutive securities excluded from computation of EPS	600	400	600	200

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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