Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 32,976	$ 31,653
Short-term investments		2,804
Patient receivables, net of allowances of $920 and $1,019, respectively	3,184	2,810
Other accounts receivable, net	2,139	443
Prepaid expenses and other	4,272	3,318
Total current assets	42,571	41,028
Property and equipment, net	5,954	6,380
Patient receivables, net of allowances of $619 and $634, respectively	1,310	1,059
Other assets	225	501
Total assets	50,060	48,968
Current liabilities
Accounts payable	8,239	8,046
Accrued liabilities and other	12,338	11,930
Total current liabilities	20,577	19,976
Other long-term liabilities	2,907	3,454
Long-term insurance reserves, less current portion	5,556	5,741
Stockholders' investment
Common stock ($.001 par value; 25,291,637 shares issued and 19,186,615 and 19,050,504 shares outstanding, respectively)	25	25
Contributed capital	179,889	179,543
Common stock in treasury, at cost (6,105,022 shares and 6,241,133 shares, respectively)	(110,332)	(111,395)
Accumulated deficit	(49,142)	(49,053)
Accumulated other comprehensive income	580	677
Total stockholders' investment	21,020	19,797
Total liabilities and stockholders' investment	$ 50,060	$ 48,968