Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]

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- Definition

Number of share-based compensation awards forfeited or expired in Period

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Grants in Period, Gross

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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STOCK-BASED COMPENSATION (Stock Award Plans) (Details) - shares	1 Months Ended	12 Months Ended	120 Months Ended	168 Months Ended
	May 31, 2014	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of option awards exercised (in shares)		267,399
Employee Stock Award Plan-2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration term		10 years
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Beginning balance (in shares)		996,828	1,900,000
Additional shares authorized (in shares)	1,500,000	0	1,500,000
Number of awards granted (in shares)		(151,096)	(3,023,067)
Number of awards forfeited or expired (in shares)		45,125	513,924
Ending balance (in shares)		890,857	890,857	890,857
Employee Stock Award Plan-2008 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of option awards exercised (in shares)		238,719	1,324,614
Employee Stock Award Plan-2008 \| Unrestricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of awards granted (in shares)		(900)	(9,370)
Employee Stock Award Plan-2008 \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of restricted stock awards vested (in shares)		20,025	58,193
Director Plan - 2005
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Beginning balance (in shares)		61,813		300,000
Number of awards granted (in shares)		(12,650)		(274,840)
Number of awards forfeited or expired (in shares)		0		24,003
Ending balance (in shares)		49,163	49,163	49,163
Director Plan - 2005 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of option awards exercised (in shares)		28,680		117,961
Director Plan - 2005 \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of restricted stock awards vested (in shares)		17,269		71,541
Minimum \| Employee Stock Award Plan-2008 \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of restricted stock awards		3 years
Maximum \| Employee Stock Award Plan-2008 \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of restricted stock awards		5 years
Tranche one \| Employee Stock Award Plan-2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of option awards vest and exercisable in installments		20.00%
Tranche two \| Employee Stock Award Plan-2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of option awards vest and exercisable in installments		33.30%