CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Revenues:
Product	$ 928,129	$ 743,838	$ 799,002
Service	478,681	463,610	458,731
Total revenues	1,406,810	1,207,448	1,257,733
Cost of revenues:
Product	551,995	494,463	454,988
Service	286,350	266,823	263,564
Total cost of revenues	838,345	761,286	718,552
Gross Profit	568,465	446,162	539,181
Operating expenses:
Selling, general, and administrative	309,552	325,468	296,613
Research and development	35,953	34,280	34,008
Restructuring expenses	644	1,202	4,848
Total operating expenses	346,149	360,950	335,469
Income from operations	222,316	85,212	203,712
Non-operating expenses, net:
Interest expense	12,065	12,000	13,171
Interest income and miscellaneous expense	(857)	(607)	(1,275)
Total non-operating expenses, net	11,208	11,393	11,896
Income before income tax expense (benefit)	211,108	73,819	191,816
Income tax expense	74,993	22,554	63,349
Net income	$ 136,115	$ 51,265	$ 128,467
Net income per common share
Basic	$ 2.33	$ 0.86	$ 2.18
Diluted	$ 2.31	$ 0.85	$ 2.16
Cash dividends declared per common share outstanding	$ 0.66	$ 0.56	$ 2.44