Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Assets
Cash and cash equivalents	$ 22,914	$ 18,568
Short-term investments	24,520	25,311
Patient receivables, net of allowances of $1,002 and $1,035	2,895	2,366
Other accounts receivable, net	2,945	1,974
Prepaid expenses and other	3,714	4,254
Total current assets	56,988	52,473
Property and equipment, net	9,389	10,637
Long-term investments	882	902
Patient receivables, net of allowances of $719 and $634	1,099	769
Other assets	1,349	1,652
Total assets	69,707	66,433
Liabilities and Stockholders' Investment
Accounts payable	9,534	8,103
Accrued liabilities and other	12,129	12,175
Deferred revenue	2,064	2,516
Debt obligations maturing within one year	3,015	2,978
Total current liabilities	26,742	25,772
Long-term insurance reserves, less current portion	6,183	6,264
Long-term debt obligations, less current portion	258	1,026
Other long-term liabilities	6,124	7,106
Stockholders' investment
Common stock ($.001 par value; 25,291,637 shares issued and 18,972,134 and 18,858,147 shares outstanding, respectively)	25	25
Contributed capital	177,790	177,287
Common stock in treasury, at cost (6,319,503 shares and 6,433,490 shares, respectively)	(112,047)	(112,910)
Accumulated deficit	(36,041)	(38,720)
Accumulated other comprehensive income	673	583
Total stockholders' investment	30,400	26,265
Total liabilities and stockholders' investment	$ 69,707	$ 66,433