CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011
Current assets:
Cash and cash equivalents	$ 167,234	$ 228,993	$ 158,235
Short-term investments	0	148,488	147,136
Restricted cash	751	2,128	387
Accounts receivable, net	73,675	48,106	47,041
Deferred income taxes	16,859	9,759	4,804
Prepaid expenses and other current assets	14,571	18,814	24,567
Total current assets	273,090	456,288	382,170
Property and equipment, net	198,175	201,257	198,207
Deferred income taxes	36,016	33,267	33,165
Other assets	49,360	38,006	45,610
Total assets	556,641	728,818	659,152
Current liabilities:
Accounts payable	80,777	78,876	66,008
Accrued compensation and benefits	25,711	21,438	23,610
Other current liabilities	19,454	18,190	8,421
Deferred revenue	121,873	226,543	266,847
Total current liabilities	247,815	345,047	364,886
Long-term debt	150,000	150,000	150,000
Other liabilities	74,615	64,972	57,791
Total liabilities	472,430	560,019	572,677
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 issued	371	371	371
Capital surplus	198,812	189,573	181,954
Retained earnings	925,781	827,675	684,905
Accumulated other comprehensive (loss)	(9,147)	(9,479)	(4,438)
Treasury stock, 13,749,764, 10,969,425 and 10,045,948 shares, at cost	(1,031,606)	(839,341)	(776,317)
Total shareholders' equity	84,211	168,799	86,475
Total liabilities and shareholders' equity	$ 556,641	$ 728,818	$ 659,152