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STOCK-BASED COMPENSATION Valuation Assumptions (Details) (Stock Options [Member], USD $)	3 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	41.70%	44.40%
Risk-free interest rate	0.60%	1.40%
Expected dividends	1.30%	0.60%
Expected life (in years)	4 years 110 days	4 years
Weighted-average grant date fair value	$ 10.30	$ 12.58

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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