SHARE-BASED COMPENSATION Weighted Average Assumptions Used in Estimating the Value of Performance Share Units Granted (Details) - Performance share units	6 Months Ended
Jun. 30, 2019 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award
Valuation date average stock price(1)	$ 25.83
Expected dividends	5.25%
Risk-free rate minimum	2.43%
Risk-free rate maximum	2.55%
Expected volatility minimum	22.50%
Expected volatility maximum	27.40%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Performance period	Jan. 01, 2019
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Performance period	Dec. 31, 2021

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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- Definition

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

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Performance Period.

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