Condensed Consolidated Balance Sheets (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010
Assets
Cash and cash equivalents	$ 158,235	$ 163,779	$ 140,524
Short-term investments	147,136	149,160	139,486
Restricted cash	387	255	70
Accounts receivable, net	47,041	68,937	98,390
Deferred income taxes	4,804	9,079	17,141
Prepaid expenses and other current assets	24,567	22,887	16,671
Total current assets	382,170	414,097	412,282
Property and equipment, net	198,207	198,213	193,717
Deferred income taxes	33,165	21,814	12,237
Other assets	45,610	40,656	28,008
Total assets	659,152	674,780	646,244
Liabilities and Shareholders' Equity
Accounts payable	66,008	67,920	76,116
Accrued compensation and benefits	23,610	28,428	26,049
Other current liabilities	8,421	15,441	14,491
Deferred revenue	266,847	244,362	197,107
Total current liabilities	364,886	356,151	313,763
Long-term debt	150,000	150,000	150,000
Other liabilities	57,791	40,559	29,049
Total liabilities	572,677	546,710	492,812
Shareholders' equity:
Preferred stock, $.01 par value, 5,000,000 shares authorized, none issued	0	0	0
Common stock, $.01 par value, 300,000,000 shares authorized, 37,068,904, 37,068,904 and 54,068,904 issued	371	371	541
Capital surplus	181,954	173,935	165,678
Retained earnings	684,905	524,678	1,182,204
Accumulated other comprehensive (loss)	(4,438)	(4,509)	(9,555)
Treasury stock, 10,045,948, 7,075,563 and 20,478,818 shares, at cost	(776,317)	(566,405)	(1,185,436)
Total shareholders' equity	86,475	128,070	153,432
Total liabilities and shareholders' equity	$ 659,152	$ 674,780	$ 646,244