Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current assets
Cash and cash equivalents	$ 31,186	$ 18,568
Short-term investments	2,804	25,311
Patient receivables, net of allowances of $1,034 and $1,035, respectively	2,998	2,366
Other accounts receivable, net	2,043	1,974
Prepaid expenses and other	3,210	4,254
Total current assets	42,241	52,473
Property and equipment, net	7,788	10,637
Long-term investments	923	902
Patient receivables, net of allowances of $705 and $634	1,177	769
Other assets	777	1,652
Total assets	52,906	66,433
Current liabilities
Accounts payable	5,443	8,103
Accrued liabilities and other	11,283	12,175
Deferred revenue	1,229	2,516
Debt obligations maturing within one year		2,978
Total current liabilities	17,955	25,772
Long-term insurance reserves, less current portion	5,988	6,264
Long-term debt obligations, less current portion		1,026
Other long-term liabilities	4,164	7,106
Stockholders' investment
Common stock ($.001 par value; 25,291,637 shares issued and 19,024,305 and 18,858,147 shares outstanding, respectively)	25	25
Contributed capital	178,818	177,287
Common stock in treasury, at cost (6,267,332 shares and 6,433,490 shares, respectively)	(111,658)	(112,910)
Accumulated deficit	(43,166)	(38,720)
Accumulated other comprehensive income	780	583
Total stockholders' investment	24,799	26,265
Total liabilities and stockholders' investment	$ 52,906	$ 66,433