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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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).

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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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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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STOCK-BASED COMPENSATION PLANS (Details) - $ / shares			3 Months Ended	6 Months Ended
STOCK-BASED COMPENSATION PLANS (Details) - $ / shares	Mar. 13, 2015	Mar. 06, 2015	Jun. 30, 2015	Jun. 30, 2015	May. 01, 2015	Dec. 31, 2014
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					$ 38.36	$ 39.84
Share-based compensation, unrestricted stock awards issued			3,030	84
Restricted Stock \| Equity and Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, number of shares vested		6,281.00
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