STOCK-BASED COMPENSATION PLANS: (Details 3) (Stock Options, USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2014	Apr. 30, 2014
Stock Options
STOCK-BASED COMPENSATION PLANS:
Number of shares to be granted annually			125,000
Aggregate intrinsic value	$ 20	$ 20
Weighted average remaining contractual life		10 years
Compensation expense	$ 1.1	$ 1.5
Assumptions used in valuation
Exercise price	$ 27.36	$ 27.36
Risk-free interest rate (as a percent)		1.80%
Expected life		5 years
Expected volatility (as a percent)		47.60%
Annual dividend yield (as a percent)		2.30%

Represents the number of shares available to be granted annually under the agreement.

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Name Staff Accounting Bulletin (SAB)

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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- Definition

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.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated measure of the 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 risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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