Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Condensed Consolidated Balance Sheets
Allowances for patient receivables, current	$ 1,223	$ 1,392
Allowances for patient receivables, non-current	$ 542	$ 330
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares issued	25,291,637	25,291,637
Common stock, shares outstanding	18,837,847	18,711,365
Treasury stock, shares	6,453,790	6,580,272

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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A valuation allowance for receivables due to an Entity for more than one year from the balance sheet date that are expected to be uncollectible.

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-Publisher SEC
-Name Regulation S-X (SX)
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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Shares outstanding equals shares issued minus shares held in treasury and other adjustments, if any.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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