Fair Value Measurements (Details) - USD ($) $ in Thousands	Jul. 02, 2016	Apr. 02, 2016
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale Securities, Noncurrent	$ 209,015	$ 220,807
Fair Value, Inputs, Level 3 [Member] | Auction Rate Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Available-for-sale Securities, Noncurrent	10,068
Fair Value, Measurements, Recurring [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	3,647,209	3,493,066
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	329,520	314,571
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	3,307,621	3,168,518
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	10,068	9,977
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Money Market Funds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	275,694	232,698
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	28,765
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	159,932	104,964
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value		1,003
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	37,971	98,967
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	275,694	232,698
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value		0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	28,765
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	159,932	104,964
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value		1,003
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	37,971	98,967
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value		0
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value		0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	479,779	284,853
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	426,673	460,148
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | U.S. Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	97,398	192,293
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	51,203	61,579
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	234,731	214,201
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	1,093,508	1,067,157
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	33,718	35,116
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Bank Loans [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	98,318	102,015
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	208,635	210,051
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Commercial Mortgage Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	211,653	206,470
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	53,826	81,873
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Bank Loans [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Mortgage Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	479,779	284,853
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	426,673	460,148
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	43,572	110,420
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	51,203	61,579
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	234,731	214,201
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	1,093,508	1,067,157
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	33,718	35,116
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Loans [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	98,318	102,015
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	208,635	210,051
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Mortgage Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	211,653	206,470
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Non-financial institution securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign Government and Agency Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Bank Loans [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Mortgage Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	5,734	7,100
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	129,601	140,382
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	57,335	56,785
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	6,277	6,563
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Auction Rate Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value		9,977
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Derivative Financial Instruments, Assets [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	216	744
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Auction Rate Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Derivative Financial Instruments, Assets [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	5,734	7,100
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	129,601	140,382
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	57,335	56,785
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	6,277	6,563
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Auction Rate Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative Financial Instruments, Assets [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	216	744
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Mutual Fund [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	0	0
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Auction Rate Securities [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	10,068	9,977
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member]
Assets and Liabilities Measured at Fair Value on a Recurring Basis
Assets measured at fair value	$ 0	$ 0