v2.4.0.6

Cash and cash equivalents and marketable securities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash and cash equivalents:
Cash	$ 16,677	$ 12,851
Money market accounts	39,001	81,082
Marketable securities	2,460
Total cash and cash equivalents	58,138	93,933	25,721	22,629
Short-term marketable securities available-for-sale:
Marketable securities	41,558
Total short-term marketable securities	41,558	0
Interest income	$ 183	$ 37	$ 31

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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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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