SHARE-BASED COMPENSATION (Summary of Stock Options Outstanding) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Feb. 26, 2009
Options outstanding
Number of option	4,878,097	7,356,249	6,962,675
Weighted average contractual period	5 years	5 years	5 years
Weighted average exercise price per option	$ 1.40	$ 1.40	$ 1.40	$ 3.30
Aggregate intrinsic value	$ 17,957	$ 8,984	$ 34,604
Options exercisable
Number of options	2,839,857	2,195,234	1,098,300
Weighted average exercise price per option	$ 1.40	$ 1.40	$ 1.40
Aggregate intrinsic value	$ 2,507	$ 2,106	$ 1,394

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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