Fair Value Measurements (Details) (USD $) | Dec. 28, 2013 | Mar. 30, 2013 |
In Thousands, unless otherwise specified |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Derivative asset | $473 | ' |
Fair Value, Inputs, Level 1 [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Derivative asset | 0 | ' |
Fair Value, Inputs, Level 2 [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Derivative asset | 473 | ' |
Fair Value, Inputs, Level 3 [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Derivative asset | 0 | ' |
Fair Value, Measurements, Recurring [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 3,677,777 | 3,289,221 |
Derivative Liability | ' | 1,615 |
Fair Value Liabilities, Convertible debentures - embedded derivative | 628 | 1,090 |
Total liabilities measured at fair value | 628 | 2,705 |
Net assets measured at fair value | 3,677,149 | 3,286,516 |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 780,318 | 675,379 |
Derivative Liability | ' | 0 |
Fair Value Liabilities, Convertible debentures - embedded derivative | 0 | 0 |
Total liabilities measured at fair value | 0 | 0 |
Net assets measured at fair value | 780,318 | 675,379 |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 2,877,603 | 2,585,142 |
Derivative Liability | ' | 1,615 |
Fair Value Liabilities, Convertible debentures - embedded derivative | 0 | 0 |
Total liabilities measured at fair value | 0 | 1,615 |
Net assets measured at fair value | 2,877,603 | 2,583,527 |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 19,856 | 28,700 |
Derivative Liability | ' | 0 |
Fair Value Liabilities, Convertible debentures - embedded derivative | 628 | 1,090 |
Total liabilities measured at fair value | 628 | 1,090 |
Net assets measured at fair value | 19,228 | 27,610 |
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 | ' | ' |
Total assets measured at fair value | 152,160 | 108,311 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 29,996 | 79,995 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 19,996 | 208,667 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 172,237 | ' |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | U.S. Government and Agency Securities [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 109,996 | 95,039 |
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 | ' | ' |
Total assets measured at fair value | 79,987 | 54,989 |
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 | ' | ' |
Total assets measured at fair value | 152,160 | 108,311 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | ' |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [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 | ' | ' |
Total assets measured at fair value | 109,996 | 95,039 |
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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 29,996 | 79,995 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 19,996 | 208,667 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 172,237 | ' |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
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 | ' | ' |
Total assets measured at fair value | 79,987 | 54,989 |
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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | ' |
Fair Value, Measurements, Recurring [Member] | Cash And Cash Equivalents [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 | ' | ' |
Total assets measured at fair value | 0 | 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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 109,960 | 44,992 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 179,978 | 294,883 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 310,845 | 40,728 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Municipal Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 11,990 | 3,706 |
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 | ' | ' |
Total assets measured at fair value | 664,360 | 491,898 |
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 | ' | ' |
Total assets measured at fair value | 229,940 | 214,912 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Mortgage-Backed Securities [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 318,467 | 68 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 506,442 | 416,887 |
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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 109,960 | 44,992 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 179,978 | 294,883 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 310,845 | 40,728 |
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 | ' | ' |
Total assets measured at fair value | 11,990 | 3,706 |
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 | ' | ' |
Total assets measured at fair value | 157,918 | 75,011 |
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 | ' | ' |
Total assets measured at fair value | 229,940 | 214,912 |
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 | ' | ' |
Total assets measured at fair value | 318,467 | 68 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Bank Certificates of Deposit [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Short-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total 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 | ' | ' |
Total 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 | ' | ' |
Total 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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 229,290 | 235,275 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Auction Rate Securities [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 19,856 | 28,700 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Municipal Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 17,869 | 21,234 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | U.S. Government and Agency Securities [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 55,990 | 110,285 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Mortgage-Backed Securities [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 908,906 | 1,192,612 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Debt Mutual Fund [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 55,481 | 62,927 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Long-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 | ' | ' |
Total assets measured at fair value | 11,720 | 55,142 |
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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total assets measured at fair value | 229,290 | 235,275 |
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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 17,869 | 21,234 |
Fair Value, Measurements, Recurring [Member] | Long-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 | ' | ' |
Total assets measured at fair value | 44,270 | 55,143 |
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 | ' | ' |
Total assets measured at fair value | 908,906 | 1,192,612 |
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 | ' | ' |
Total assets measured at fair value | 55,481 | 62,927 |
Fair Value, Measurements, Recurring [Member] | Long-Term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Bonds [Member] | ' | ' |
Assets and Liabilities Measured at Fair Value on a Recurring Basis | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | 19,856 | 28,700 |
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 | ' | ' |
Total assets measured at fair value | 0 | 0 |
Fair Value, Measurements, Recurring [Member] | Long-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 | ' | ' |
Total 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 | ' | ' |
Total 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 | ' | ' |
Total assets measured at fair value | $0 | $0 |