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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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Discount rate from fair value on purchase date that participants pay for shares.

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-Publisher FASB

-Name Accounting Standards Codification

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The number of grants made 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

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-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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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).

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-Publisher FASB

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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

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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Price of a single share of a number of saleable stocks of a company.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Section 02

-Paragraph 29, 30

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STOCK-BASED COMPENSATION PLANS (Details) (USD $)	0 Months Ended		3 Months Ended
STOCK-BASED COMPENSATION PLANS (Details) (USD $)	Mar. 06, 2015	Mar. 13, 2015	Dec. 31, 2014
Long Term Performance Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, number of shares vested	6,281
Management Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period	2 years
Stock based compensation, shares granted	9,379
Share-based compensation, purchase date (percent)	33.00%
Share price	37.31
Defined Contribution Retirement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period, weighted average grant date fair value		$ 38.85
Stock based compensation, shares granted		2,406
Independent Directors' Equity Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price			$ 39.84
Share-based compensation, unrestricted stock awards issued			84
Restricted Stock \| Equity and Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period, weighted average grant date fair value	37.31
Stock based compensation, vesting period	3 years