Condensed Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues	$ 414,613	$ 396,243	$ 821,791	$ 791,471
Operating expenses
Direct cost of revenues	259,528	248,220	518,008	493,838
Selling, general and administrative expense	96,325	92,460	192,972	195,049
Special charges		26,782	427	26,782
Acquisition-related contingent consideration	(7,452)	(3,541)	(6,721)	(2,984)
Amortization of other intangible assets	5,953	5,490	11,517	11,007
Costs and Expenses, Total	354,354	369,411	716,203	723,692
Operating income	60,259	26,832	105,588	67,779
Other income (expense)
Interest income and other	(387)	(363)	550	2,919
Interest expense	(13,071)	(15,195)	(25,786)	(30,399)
Other (expense) income	(13,458)	(15,558)	(25,236)	(27,480)
Income before income tax provision	46,801	11,274	80,352	40,299
Income tax provision	23,315	3,527	33,186	14,121
Net income	23,486	7,747	47,166	26,178
Earnings per common share-basic	$ 0.60	$ 0.19	$ 1.20	$ 0.65
Earnings per common share-diluted	$ 0.58	$ 0.18	$ 1.17	$ 0.61
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of tax $0	(11,714)	(10,960)	(27,223)	1,889
Other comprehensive income (loss), net of tax	(11,714)	(10,960)	(27,223)	1,889
Comprehensive income (loss)	$ 11,772	$ (3,213)	$ 19,943	$ 28,067