CONDENSED CONSOLIDATED STATEMENTS OF INCOME (PARENTHETICAL) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 17,134		$ 8,258		$ 25,798		$ 16,114
Cost of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	2,614	[1]	1,608	[1]	3,924	[1]	3,007	[1]
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	6,358		3,556		10,390		6,969
Selling General And Administrative Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 11,581		$ 4,320		$ 16,225		$ 8,532

[1] During the three and six months ended September 30, 2012, $1.8 million and $3.5 million, respectively, of share-based compensation expense was capitalized to inventory and $2.6 million and $3.9 million, respectively, of previously capitalized share-based compensation expenses in inventory was sold. During the three and six months ended September 30, 2011, $1.7 million and $3.3 million, respectively, of share-based compensation expense was capitalized to inventory and $1.6 million and $3.0 million, respectively, of previously capitalized share-based compensation expense in inventory was sold.