FAIR VALUE (Detail) (USD $) | Mar. 31, 2015 | Dec. 31, 2014 |
Carrying Amount | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | $10,804,476 | $10,703,126 |
Carrying Amount | Short-term investments (money market funds and accrued income) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 86,747 | 94,595 |
Carrying Amount | Obligations of U.S. Treasury, U.S. government corporations and agencies | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 1,818,006 | 2,020,786 |
Carrying Amount | Mortgaged-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 65,519 | 69,532 |
Carrying Amount | Certificates of deposit | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 2,008,985 | 1,975,245 |
Carrying Amount | Corporate debt securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 6,825,219 | 6,542,968 |
Estimate of Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments (money market funds and accrued income) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Obligations of U.S. Treasury, U.S. government corporations and agencies | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgaged-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Certificates of deposit | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Significant Other Observable Inputs (Level 2) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 10,804,476 | 10,703,126 |
Estimate of Fair Value | Significant Other Observable Inputs (Level 2) | Short-term investments (money market funds and accrued income) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 86,747 | 94,595 |
Estimate of Fair Value | Significant Other Observable Inputs (Level 2) | Obligations of U.S. Treasury, U.S. government corporations and agencies | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 1,818,006 | 2,020,786 |
Estimate of Fair Value | Significant Other Observable Inputs (Level 2) | Mortgaged-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 65,519 | 69,532 |
Estimate of Fair Value | Significant Other Observable Inputs (Level 2) | Certificates of deposit | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 2,008,985 | 1,975,245 |
Estimate of Fair Value | Significant Other Observable Inputs (Level 2) | Corporate debt securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 6,825,219 | 6,542,968 |
Estimate of Fair Value | Significant Unobservable Inputs (Level 3) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Significant Unobservable Inputs (Level 3) | Short-term investments (money market funds and accrued income) | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Significant Unobservable Inputs (Level 3) | Obligations of U.S. Treasury, U.S. government corporations and agencies | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Significant Unobservable Inputs (Level 3) | Mortgaged-backed securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Significant Unobservable Inputs (Level 3) | Certificates of deposit | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | 0 | 0 |
Estimate of Fair Value | Significant Unobservable Inputs (Level 3) | Corporate debt securities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Total available-for-sale securities | $0 | $0 |