Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Apr. 02, 2011
Assets
Total assets measured at fair value	$ 3,063,038	$ 2,608,477
Liabilities
Derivative financial instruments, net	3,070
Fair Value Liabilities, Convertible debentures - embedded derivative	931	945
Total liabilities measured at fair value	4,001	945
Net assets measured at fair value	3,059,037	2,607,532
Fair Value, Inputs, Level 1 [Member]
Assets
Total assets measured at fair value	647,355	327,939
Liabilities
Derivative financial instruments, net
Fair Value Liabilities, Convertible debentures - embedded derivative
Total liabilities measured at fair value
Net assets measured at fair value	647,355	327,939
Fair Value, Inputs, Level 2 [Member]
Assets
Total assets measured at fair value	2,386,754	2,245,588
Liabilities
Derivative financial instruments, net	3,070
Fair Value Liabilities, Convertible debentures - embedded derivative
Total liabilities measured at fair value	3,070
Net assets measured at fair value	2,383,684	2,245,588
Fair Value, Inputs, Level 3 [Member]
Assets
Total assets measured at fair value	28,929	34,950
Liabilities
Derivative financial instruments, net
Fair Value Liabilities, Convertible debentures - embedded derivative	931	945
Total liabilities measured at fair value	931	945
Net assets measured at fair value	27,998	34,005
Cash And Cash Equivalents [Member] | Money Market Funds [Member]
Assets
Total assets measured at fair value	232,017	275,596
Cash And Cash Equivalents [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value	29,994	79,984
Cash And Cash Equivalents [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value	233,980	485,315
Cash And Cash Equivalents [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	160,021	129,972
Cash And Cash Equivalents [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value	68,993	161,970
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]
Assets
Total assets measured at fair value	232,017	275,596
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	75,036	29,998
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value	29,994	79,984
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value	233,980	485,315
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	84,985	99,974
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value	68,993	161,970
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value	129,978	10,000
Short-Term Investments [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value	360,887	224,896
Short-Term Investments [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value	14,257
Short-Term Investments [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value		45
Short-Term Investments [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	442,694	22,400
Short-Term Investments [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value	180,958	384,428
Short-Term Investments [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value		62,261
Short-Term Investments [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value	31	24
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	322,763	14,404
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value	129,978	10,000
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value	360,887	224,896
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value	14,257
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value		45
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	119,931	7,996
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value	180,958	384,428
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value		62,261
Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value	31	24
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Bank Certificates of Deposit [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value
Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value	175,415	25,566
Long-Term Investments [Member] | Auction Rate Securities [Member]
Assets
Total assets measured at fair value	28,929	34,950
Long-Term Investments [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value	26,160	16,913
Long-Term Investments [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	66,198	53,511
Long-Term Investments [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value		29,869
Long-Term Investments [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value	892,745	605,643
Long-Term Investments [Member] | Debt Mutual Fund [Member]
Assets
Total assets measured at fair value	19,781
Long-Term Investments [Member] | Derivative financial instruments, net [Member]
Assets
Total assets measured at fair value		5,134
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Auction Rate Securities [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	17,539	7,941
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Mutual Fund [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Derivative financial instruments, net [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value	175,415	25,566
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Auction Rate Securities [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value	26,160	16,913
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value	48,659	45,570
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value		29,869
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value	892,745	605,643
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Mutual Fund [Member]
Assets
Total assets measured at fair value	19,781
Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative financial instruments, net [Member]
Assets
Total assets measured at fair value		5,134
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Bonds [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Auction Rate Securities [Member]
Assets
Total assets measured at fair value	28,929	34,950
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Government and Agency Securities [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Floating Rate Notes [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Securities [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Mutual Fund [Member]
Assets
Total assets measured at fair value
Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative financial instruments, net [Member]
Assets
Total assets measured at fair value