Investments and Fair Value Measurements (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 28, 2014	Mar. 29, 2014
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	$ 143,022	$ 184,015
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	143,022	184,015
Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	140,872	181,865
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	2,150	2,150
U.S. government/agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	102,064	133,065
U.S. government/agency securities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	102,064	133,065
U.S. government/agency securities [Member] | Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	102,064	133,065
Auction Rate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	2,150	2,150
Auction Rate Securities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	2,150	2,150
Auction Rate Securities [Member] | Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	2,150	2,150
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	38,808	48,800
Money Market Funds [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	38,808	48,800
Money Market Funds [Member] | Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of financial assets measured at fair value on a recurring basis	$ 38,808	$ 48,800