Number of common stock shares awarded as restricted stock or restricted stock units, maximum.

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- Definition

Sharebased Compensation Arrangement By Sharebased Payment Award Award Assumption Based Shares Earned Percentage

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Assumption Based Shares Earned

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Assumption Based Shares Earned, Target

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Term Of Plan

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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

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 weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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 highest quantity of shares an employee can purchase under the plan per period.

+ 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=96867065&loc=d3e5070-113901

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ 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 (d)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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STOCK-BASED COMPENSATION PLANS - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised	$ 748	$ 760	$ 708
Unrecognized compensation cost	$ 1,700
Unrecognized compensation cost, expense recognition period	2 years 1 month 6 days
ISOP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	1,012,500
Term of plan	10 years
ISOP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
ISOP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	7 years
2009 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	393,750
Term of plan	10 years
Number of common stock shares awarded as RSA's, maximum	168,750
Stock award granted to one individual, maximum	45,000
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	420,000
Term of plan	10 years
Stock award granted to one individual, maximum	30,000
Shares available for grant under this plan	185,223
Long Term Incentive Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of plan	3 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 64
Unrecognized compensation cost, expense recognition period	1 year 22 days
Stock options \| Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, expense recognition period	6 years
Stock options and restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit recognized from compensation expense	$ 308	274	135
Restricted stock units and performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit recognized from compensation expense	$ 423	$ 320	$ 214
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair market value on granted shares (usd per share)	$ 26.74	$ 21.02
Performance period required	3 years	3 years
Current assumption based shares earned, percentage	20.71%	129.86%
Current assumptions base shares earned, target shares	13,318	13,969
Current assumptions base shares earned, shares	2,758	18,140
Performance stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	0	0
Performance stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance	19,973	20,949
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Fair market value on granted shares (usd per share)	$ 28.48	$ 23.20
Restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair market value on granted shares (usd per share)	26.86	22.95
Restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair market value on granted shares (usd per share)	$ 30.93	$ 24.57