Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 32,418	$ 45,479
Accounts receivable, net of allowances of $2,607 and $2,893	238,702	230,613
Prepaid expenses and other current assets	12,462	8,033
Prepaid income taxes	1,799	2,378
Deferred income taxes	4,813	4,724
Total current assets	290,194	291,227
Property and equipment, net of accumulated depreciation of $86,619 and $82,512	21,035	20,528
Deferred income taxes	5,036	5,260
Goodwill	62,808	62,280
Other intangible assets, net	14,408	15,157
Other non-current assets	11,144	11,355
Total assets	404,625	405,807
Current liabilities:
Short-term borrowings	1,618	2,812
Accounts payable	32,883	38,019
Accrued compensation and related expenses	51,159	46,123
Other accrued expenses and other current liabilities	12,381	16,037
Income taxes payable	530	245
Total current liabilities	98,571	103,236
Deferred compensation	8,759	9,393
Deferred income tax	4,277	2,994
Other non-current liabilities	4,800	5,010
Total liabilities	116,407	120,633
Commitments and contingencies
Equity:
Preferred stock, $0.10 par value - authorized 1,000 shares; none issued	0	0
Common stock	2,206	2,196
Additional paid-in-capital	70,970	70,104
Retained earnings	266,596	265,207
Accumulated other comprehensive (loss) income	38	(712)
Common stock in treasury, at cost - 2,463 shares	(52,487)	(52,487)
Total CDI shareholders' equity	287,323	284,308
Noncontrolling interest	895	866
Total equity	288,218	285,174
Total liabilities and equity	404,625	405,807
Common Class B [Member]
Equity:
Common stock	$ 0	$ 0