STOCK-BASED COMPENSATION Valuation Assumptions (Details) - $ / shares	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	26.70%		27.20%	28.40%
Risk-free interest rate	1.40%		1.30%	1.40%
Expected dividend yield	1.10%		1.10%	1.40%
Expected life (in years)	4 years 73 days		4 years 73 days	4 years 73 days
Weighted-average grant date fair value	$ 12.02		$ 11.54	$ 9.21
Stock options granted		0	156,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	21.90%	24.80%	21.90%	24.80%
Risk-free interest rate	0.30%	0.10%	0.30%	0.10%
Expected dividend yield	1.10%	1.30%	1.10%	1.30%
Expected life (in years)	183 days	183 days	183 days	183 days
Weighted-average grant date fair value	$ 11.73	$ 10.13	$ 11.73	$ 10.13