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

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Percentage Vested And Exercisable Each Year

+ References

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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.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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-Publisher FASB
-Name Accounting Standards Codification
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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.

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No definition available.

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- Definition

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

+ References

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

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-Publisher FASB
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-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

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

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-Name Accounting Standards Codification
-Topic 210
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STOCK-BASED COMPENSATION (Stock Award Plans) (Details) - shares	1 Months Ended	12 Months Ended	108 Months Ended	156 Months Ended
	May 31, 2014	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Number of option awards exercised (in shares)		173,635
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%
Award expiration term		10 years
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Beginning balance (in shares)		1,248,651	1,900,000
Additional shares authorized (in shares)	1,500,000	0	1,500,000
Number of awards granted (in shares)		(259,405)	(2,871,971)
Number of awards forfeited or expired (in shares)		7,582	468,799
Ending balance (in shares)		996,828	996,828	996,828
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)		136,827	1,085,895
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)		(1,145)	(8,470)
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)		1,198	38,168
Director Plan - 2005
Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]
Beginning balance (in shares)		74,771		300,000
Number of awards granted (in shares)		(12,958)		(262,190)
Number of awards forfeited or expired (in shares)		0		24,003
Ending balance (in shares)		61,813	61,813	61,813
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)		36,808		89,281
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)		22,716		54,272
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