STOCK-BASED COMPENSATION (Details 3) (USD $)	12 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable (in shares)	2,976,870
Options outstanding (in shares)	4,133,753
Under $16
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	$ 0.00
Range of exercise price, maximum, (in dollars per share)	$ 16.00
Options exercisable (in shares)	939,928
Weighted average exercise price, exercisable (in dollars per share)	$ 15.03
Options outstanding (in shares)	939,928
Weighted average exercise price, outstanding (in dollars per share)	$ 15.03
$16-$20
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	$ 16.00
Range of exercise price, maximum, (in dollars per share)	$ 20.00
Options exercisable (in shares)	766,746
Weighted average exercise price, exercisable (in dollars per share)	$ 18.01
Options outstanding (in shares)	766,746
Weighted average exercise price, outstanding (in dollars per share)	$ 18.01
Over $20
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	$ 20.00
Options exercisable (in shares)	1,270,196
Weighted average exercise price, exercisable (in dollars per share)	$ 21.37
Options outstanding (in shares)	2,427,079
Weighted average exercise price, outstanding (in dollars per share)	$ 22.80

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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