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Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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SHARE REPURCHASE (Details) (USD $)	12 Months Ended
SHARE REPURCHASE (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Oct. 26, 2012
Equity, Class of Treasury Stock [Line Items]
Repurchase of ADSs, amount	$ 12,410	$ 10,123,821	$ 14,590,355
2011 Purchase Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized ADSs to be repurchased, shares					5,000,000
Authorized ADSs to be repurchased, amount					15,000,000
Repurchase of ADSs, in shares			1,746,059	607,478
Repurchase of ADSs, amount			12,518,624	2,748,579
Cancellation of ADSs, shares				500,000
2012 Purchase Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized ADSs to be repurchased, shares						5,000,000
Authorized ADSs to be repurchased, amount						20,000,000
Repurchase of ADSs, in shares		1,592,558	362,807
Repurchase of ADSs, amount		$ 10,123,821	$ 2,071,731