Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets
Cash and cash equivalents	$ 170,578	$ 156,371
Accounts receivable, net	243,360	243,636
Prepaids and other current assets	51,737	37,434
Deferred tax assets, net	23,692	22,994
Income tax receivable	12,328	17,847
Total current assets	501,695	478,282
Long-term assets
Property, plant and equipment, net	105,055	100,321
Goodwill	72,057	70,844
Contract acquisition costs, net	2,358	2,866
Deferred tax assets, net	31,642	32,512
Other long-term assets	72,145	62,153
Total long-term assets	283,257	268,696
Total assets	784,952	746,978
Current liabilities
Accounts payable	29,960	27,555
Accrued employee compensation and benefits	71,000	71,500
Other accrued expenses	43,941	33,816
Income taxes payable	12,222	10,051
Deferred tax liabilities, net	1,745	912
Deferred revenue	16,603	15,895
Other current liabilities	8,530	10,282
Total current liabilities	184,001	170,011
Long-term liabilities
Line of credit	78,000	64,000
Negative investment in deconsolidated subsidiary	76	76
Deferred tax liabilities, net	3,226	3,020
Deferred rent	7,528	6,729
Other long-term liabilities	43,459	32,895
Total long-term liabilities	132,289	106,720
Total liabilities	316,290	276,731
Commitments and contingencies (Note 10)	0	0
Stockholders' equity
Preferred stock - $0.01 par value: 10,000,000 shares authorized; zero shares outstanding as of June 30, 2012 and December 31, 2011	0	0
Common stock - $0.01 par value; 150,000,000 shares authorized; 54,555,105 and 56,635,319 shares outstanding as of June 30, 2012 and December 31, 2011, respectively	546	566
Additional paid-in capital	346,018	350,386
Treasury stock at cost: 27,497,148 and 25,416,934 shares as of June 30, 2012 and December 31, 2011, respectively	(390,468)	(357,267)
Accumulated other comprehensive income (loss)	7,197	(5,474)
Retained earnings	491,980	470,776
Noncontrolling interest	13,389	11,260
Total stockholders' equity	468,662	470,247
Total liabilities and stockholders' equity	$ 784,952	$ 746,978