v2.4.0.6

Cash and cash equivalents and marketable securities (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010
Cash and cash equivalents:
Cash	$ 11,587		$ 12,851
Money market accounts	45,763		81,082
Total cash and cash equivalents	57,350	78,854	93,933	25,721
Short-term marketable securities available-for-sale:
Total short-term marketable securities	37,219
Interest income	$ 128	$ 29

X

- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money.

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