Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 370,955	$ 316,337
Accounts receivable, net of allowance for doubtful accounts and billing adjustments of $3.7 million and $4.1 million at 2012 and 2011, respectively	253,732	248,541
Deferred income tax assets	7,695	12,872
Prepaid expenses and other current assets	80,598	72,431
Total current assets	712,980	650,181
Goodwill	356,121	355,498
Property and equipment, net of accumulated depreciation and amortization of $365.4 million and $357.1 million at 2012 and 2011, respectively	260,900	266,608
Computer software, net of accumulated amortization of $584.2 million and $567.4 million at 2012 and 2011, respectively	205,027	215,244
Contract acquisition costs, net of accumulated amortization of $279.5 million and $295.9 million at 2012 and 2011, respectively	161,464	162,987
Equity investments	85,891	82,924
Other intangible assets, net of accumulated amortization of $43.5 million and $39.8 million at 2012 and 2011, respectively	79,440	81,250
Deferred income tax assets, net	4,970	4,069
Other assets	39,342	39,631
Total assets	1,906,135	1,858,392
Current liabilities:
Current portion of long-term debt	181,301	181,251
Accounts payable	35,827	26,095
Accrued salaries and employee benefits	13,971	33,004
Current portion of obligations under capital leases	13,201	14,363
Other current liabilities	138,734	125,863
Total current liabilities	383,034	380,576
Deferred income tax liabilities	36,064	32,889
Long-term debt, excluding current portion	34,269	39,104
Obligations under capital leases, excluding current portion	23,418	24,489
Other long-term liabilities	61,126	60,325
Total liabilities	537,911	537,383
Shareholders' equity:
Common stock - $0.10 par value. Authorized 600,000 shares; 202,447 and 201,860 issued at 2012 and 2011, respectively; 189,773 and 189,031 outstanding at 2012 and 2011, respectively	20,245	20,186
Additional paid-in capital	129,104	125,948
Accumulated other comprehensive income (loss), net	3,489	(445)
Treasury stock, at cost (shares of 12,674 and 12,829 at 2012 and 2011, respectively)	(221,927)	(225,034)
Retained earnings	1,418,140	1,380,634
Total shareholders' equity	1,349,051	1,301,289
Noncontrolling interests in consolidated subsidiaries	19,173	19,720
Total equity	1,368,224	1,321,009
Commitments and contingencies
Total liabilities and equity	$ 1,906,135	$ 1,858,392