CONOLIDATED BALANCE SHEETS (USD $) In Thousands	Mar. 31, 2011	Mar. 31, 2010
Assets [Abstract]
Cash and cash equivalents	$ 703,924	$ 492,130
Short-term investments	539,572	722,193
Accounts receivable, net	181,202	137,806
Inventories	180,800	116,579
Prepaid expenses	22,234	13,068
Deferred tax assets	88,822	77,810
Other current assets	58,429	51,383
Total current assets	1,774,983	1,610,969
Property, plant and equipment, net	540,513	493,039
Long-term investments	464,838	317,215
Goodwill	76,018	40,338
Intangible assets, net	77,929	35,527
Other assets	33,777	19,225
Total assets	2,968,058	2,516,313
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable	68,433	44,238
Accrued liabilities	131,839	60,211
Deferred income on shipments to distributors	140,044	98,941
Total current liabilities	340,316	203,390
Junior convertible debentures	347,334	340,672
Long-term income tax payable	58,125	57,140
Deferred tax liability	399,527	376,713
Other long-term liabilities	10,318	5,018
Stockholders' equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued or outstanding.	0	0
Common stock, $0.001 par value; 450,000,000 shares authorized; 218,789,994 shares issued and 189,541,707 shares outstanding at March 31, 2011; 218,789,994 shares issued and 185,329,144 shares outstanding at March 31, 2010	190	185
Additional paid-in capital	1,268,128	1,276,822
Retained earnings	1,428,838	1,266,699
Accumulated other comprehensive income	3,357	3,032
Common stock held in treasury: 29,248,287 shares at March 31, 2011; 33,460,850 shares at March 31, 2010	(888,075)	(1,013,358)
Total stockholders' equity	1,812,438	1,533,380
Total liabilities and stockholders' equity	$ 2,968,058	$ 2,516,313