Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Revenue	$ 277,916	$ 279,390	$ 810,745	$ 834,415
Cost of services	225,219	224,670	656,352	668,482
Gross profit	52,697	54,720	154,393	165,933
Operating and administrative expenses	45,751	45,711	137,292	141,671
Operating profit	6,946	9,009	17,101	24,262
Other income (expense), net	(57)	(47)	(170)	(165)
Income before income taxes	6,889	8,962	16,931	24,097
Income tax expense	2,323	3,556	6,315	9,706
Net income	4,566	5,406	10,616	14,391
Less: Income attributable to the noncontrolling interest	38	57	159	267
Net income attributable to CDI	$ 4,528	$ 5,349	$ 10,457	$ 14,124
Earnings per common share:
Basic (per share)	$ 0.23	$ 0.27	$ 0.54	$ 0.73
Diluted (per share)	$ 0.23	$ 0.27	$ 0.53	$ 0.72