Represents the intrinsic value of stock options, which are currently vested at the end of the period.

No definition available.

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- Definition

The weighted average exercise price of options that are fully vested at the end of the period and are currently exerciseable.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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.

+ 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

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: 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

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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- Definition

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.

+ 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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STOCK OPTIONS OUTSTANDING (Details 2) - Employee Stock Option [Member] - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014
Stock options outstanding
Allocated Share-based Compensation Expense		$ 0.5
Shares	3,465,674	4,104,412	3,490,421	3,313,869
Weighted Average Remaining Contractual Term (in years)	7 years 3 months 22 days
Weighted Average Exercise Price (in dollars per share)	$ 16.30	$ 16.16	$ 16.40	$ 15.89
Stock options becoming fully vested and exercisable (in shares)	1,792,875
Intrinsic value of options vested	$ 4.7
Weighted Average Exercise Price (in dollars per share)	$ 15.74
Weighted average contractual term	6 years 9 months 6 days
March 2012 [Member]
Stock options outstanding
Shares	1,101,160
Weighted Average Remaining Contractual Term (in years)	6 years
Weighted Average Exercise Price (in dollars per share)	$ 14.72
August 2012 [Member]
Stock options outstanding
Shares	36,400
Weighted Average Remaining Contractual Term (in years)	6 years 5 months 1 day
Weighted Average Exercise Price (in dollars per share)	$ 13.75
October 2012 [Member]
Stock options outstanding
Shares	276,623
Weighted Average Remaining Contractual Term (in years)	6 years 7 months
Weighted Average Exercise Price (in dollars per share)	$ 14.47
February 2013 [Member]
Stock options outstanding
Shares	520,360
Weighted Average Remaining Contractual Term (in years)	6 years 11 months 1 day
Weighted Average Exercise Price (in dollars per share)	$ 16.48
February 2014 [Member]
Stock options outstanding
Shares	596,400
Weighted Average Remaining Contractual Term (in years)	7 years 11 months
Weighted Average Exercise Price (in dollars per share)	$ 18.40
July 2014 [Member]
Stock options outstanding
Shares	25,291
Weighted Average Remaining Contractual Term (in years)	8 years 4 months
Weighted Average Exercise Price (in dollars per share)	$ 17.20
February 2015 [Member]
Stock options outstanding
Shares	709,440
Weighted Average Remaining Contractual Term (in years)	8 years 11 months
Weighted Average Exercise Price (in dollars per share)	$ 17.18
Award Issuance Period April 2015 [Member] [Domain] [Member]
Stock options outstanding
Shares	200,000
Weighted Average Remaining Contractual Term (in years)	9 years 1 month
Weighted Average Exercise Price (in dollars per share)	$ 17.98