CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Current assets:
Cash and cash equivalents	$ 228,776	$ 209,335
Short-term investments	116,581	125,177
Accounts receivable, net	128,209	111,771
Inventory, net	67,435	53,713
Deferred tax assets	10,120	11,090
Other current assets	15,369	13,088
Total current assets	566,490	524,174
Long-term investments	80,261	55,347
Property, plant and equipment, net	99,111	76,159
Goodwill and purchased intangibles, net	16,440	14,388
Other assets	2,303	2,402
Total assets	764,605	672,470
Current liabilities:
Accounts payable	37,067	34,126
Accrued liabilities	66,419	52,067
Total current liabilities	103,486	86,193
Deferred tax liabilities	1,742	8,673
Long-term income taxes payable	12,005	12,150
Revolving line of credit	0	37,000
Other long-term liabilities	925	1,210
Total liabilities	118,158	145,226
Commitments and contingencies (Note 9)
Stockholders' Equity:
Preferred stock, $0.01 par value per share; 1,000 shares authorized, no shares outstanding	0	0
Common stock, $0.01 par value per share; 100,000 shares authorized, 43,296 shares and 47,160 shares issued at 2013 and 2012, respectively	757	741
Additional paid-in capital	612,283	557,218
Accumulated other comprehensive income	5,567	6,357
Retained earnings	28,344	115,358
Total stockholders' equity before treasury stock	646,951	679,674
Less: Treasury stock (common: 13 and 4,648 shares at 2013 and 2012, respectively) at cost	(504)	(152,430)
Total stockholders' equity	646,447	527,244
Total liabilities and stockholders' equity	$ 764,605	$ 672,470