STOCK-BASED COMPENSATION (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
STOCK-BASED COMPENSATION [Abstract]
Stock-based compensation expense	$ 2.7	$ 3.7	$ 4.8	$ 5.7
Mark-to-market adjustment	(0.1)	(0.6)	0.8	0.2
Total expense	$ 2.6	$ 3.1	$ 5.6	$ 5.9
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology
Option pricing model used			Black-Scholes
Dividend yield (in hundredths)			4.32%	4.32%
Risk-free interest rate (in hundredths)			3.05%	3.00%
Expected volatility (in hundredths)			42.00%	42.00%
Expected life (years)			7.0	7.0
Grant fair value (per option)			$ 5.48	$ 4.61
Exercise price	$ 18.78	$ 15.68	$ 18.78	$ 15.68
Shares granted (in shares)			575,000	803,750

Adjustment to expense resulting from changes in the market value of underlying common stock in the liabilities associated with employee/director stock options, performance stock awards, restricted stock awards and deferred directors' compensation issued to employees and directors.

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Total equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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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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The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior.

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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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For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

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

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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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