CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net service revenues	$ 1,033,173	$ 984,668	$ 3,077,000	$ 2,803,503
Direct costs of services, consisting of payroll, payroll taxes, insurance costs and reimbursable expenses	617,924	592,765	1,844,365	1,701,223
Gross margin	415,249	391,903	1,232,635	1,102,280
Selling, general and administrative expenses	321,030	319,817	986,312	924,705
Amortization of intangible assets	100	39	187	118
Interest income, net	(348)	(148)	(867)	(598)
Income before income taxes	94,467	72,195	247,003	178,055
Provision for income taxes	36,807	28,027	95,680	70,757
Net income	57,660	44,168	151,323	107,298
Net income available to common stockholders-diluted	$ 57,383	$ 43,556	$ 150,551	$ 105,740
Net income per share (Note J):
Basic	$ 0.42	$ 0.31	$ 1.09	$ 0.75
Diluted	$ 0.41	$ 0.31	$ 1.08	$ 0.74
Shares:
Basic	137,918	139,449	138,627	141,118
Diluted	139,141	140,433	139,735	142,373
Cash dividends declared per share	$ 0.15	$ 0.14	$ 0.45	$ 0.42