Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Patient receivables, net of allowances - Current	$ 1,019	$ 1,035
Patient receivables, net of allowances - Non-current	$ 634	$ 634
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares issued	25,291,637	25,291,637
Common stock, shares outstanding	19,050,504	18,858,147
Treasury stock, shares	6,241,133	6,433,490