STOCK-BASED COMPENSATION (Details 3) (USD $)	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Share-based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions
Weighted average fair value of option grants (in dollars per share)	$ 14.32
Black-Scholes option pricing model
Share-based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions
Weighted average fair value of option grants (in dollars per share)	$ 14.32	$ 12.09	$ 13.36
Expected dividend yield (as a percent)	1.39%	1.45%	0.89%
Risk-free interest rate (as a percent)	2.37%	2.86%	3.46%
Expected volatility (as a percent)	52.64%	55.26%	56.65%
Expected lives (in years)	5.18	5.17	5.28
Monte Carlo option pricing model \| Market-based performance shares
Share-based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions
Weighted average fair value of performance shares grants (in dollars per share)	$ 11.81
Grant price per share of awards (in dollars per share)	$ 70.88
Expected dividend yield (as a percent)	1.33%
Risk-free interest rate (as a percent)	3.30%
Expected volatility (as a percent)	36.02%

Represents the grant price per share of awards based on which the weighted-average fair value per share of awards is determined.

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- Definition

The weighted average fair value at grant for nonvested share-based awards issued during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(1)

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(c)

+ Details

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- Definition

The period of time a share-based award is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(a)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section D
-Subsection 2

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- Definition

The estimated measure of the percentage amount 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(b)

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(d)

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(1)

+ Details

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