Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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-Name Accounting Standards Codification
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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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.

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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.

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Number of share options (or share units) exercised during the current period.

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SHARE-BASED PAYMENTS - Schedule of Share-based Compensation, Stock Options, Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted average exercise price, beginning of period (in dollars per share)	$ 4.48	$ 5.69	$ 6.54
Grants in period, weighted average exercise price (in dollars per share)	1.75	2.34	2.13
Exercises in period, weighted average exercise price (in dollars per share)	2.15	0.00	2.12
Forfeitures in period, weighted average exercise price (in dollars per share)	3.96	2.93	5.52
Expirations in period, weighted average exercise price (in dollars per share)	8.18	8.42	8.03
Weighted average exercise price, end of period (in dollars per share)	$ 3.84	$ 4.48	$ 5.69
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of options, beginning of period (in shares)	2,028,847	2,045,143	2,122,897
Stock options granted in period (in shares)	442,956	738,893	449,537
Number of exercises in period (in shares)	(355,092)	0	(8,369)
Number of forfeitures in period (in shares)	(213,393)	(316,289)	(317,960)
Number of expirations in period (in shares)	(170,564)	(438,900)	(200,962)
Number of options, end of period (in shares)	1,732,754	2,028,847	2,045,143
2.55 - 32.10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	$ 2.55
Upper range limit (in dollars per share)	32.10
2.12 - 2.22
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	2.12
Upper range limit (in dollars per share)	2.22
2.12
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	2.12
2.12 - 18.99
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	2.12
Upper range limit (in dollars per share)	18.99
2.95 - 32.03
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	2.95
Upper range limit (in dollars per share)	32.03
2.12 - 15.61
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	2.12
Upper range limit (in dollars per share)	15.61
1.77 - 2.35
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	1.77
Upper range limit (in dollars per share)	2.35
2.12 - 11.94
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	2.12
Upper range limit (in dollars per share)	11.94
4.48 - 12.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	4.48
Upper range limit (in dollars per share)	12.55
1.77 - 15.61
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	1.77
Upper range limit (in dollars per share)	15.61
1.70 - 2.88
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	1.70
Upper range limit (in dollars per share)	2.88
1.70 - 2.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	1.70
Upper range limit (in dollars per share)	2.55
1.70 - 6.63
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	1.70
Upper range limit (in dollars per share)	6.63
5.86 - 10.36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	5.86
Upper range limit (in dollars per share)	10.36
1.70 - 15.61
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Lower range limit (in dollars per share)	1.70
Upper range limit (in dollars per share)	$ 15.61