| Upon initial election to the Board of Directors (one-time grant)              | A stock option award to purchase 25,000 shares of common stock. (1)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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|                                                                          | An award of 20,000 shares of common stock, pro-rated for the number of full and partial calendar quarters remaining in the year.  In lieu of common stock, a director may elect to receive (i) 20,000 restricted stock units or (ii) a number of stock options based on the value of 20,000 shares of common stock and application of the Black-Scholes option valuation model, each pro-rated for the number of full and partial calendar quarters remaining in the year, such election to be made before the director commences service as a member of the Board. (2) (3) |
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| Annually                                                                      | An award of (i) 20,000 shares of restricted stock, (ii) 20,000 restricted stock units or (iii) a number of stock options based on the value of 20,000 shares of common stock and application of the Black-Scholes option valuation model, as elected by each director prior to December 15 of each year for compensation to be received in the following year. (2) (3)                                                                                                                                                                                                                |
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|                                                                          | A cash retainer of $25,000, paid quarterly in arrears for ongoing service to the Board and pro-rated for any partial year of service.  In lieu of the cash retainer, each director may elect to receive shares of restricted stock, restricted stock units or stock options based on the $25,000 retainer and application of the Black-Scholes option valuation model, such election to be made prior to December 15 of each year for compensation to be received in the following year. (3) (4)                                                                            |
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| Upon the 10th, 15th and 20th anniversary of service on the Board of Directors | A stock option award to purchase 20,000 shares, 25,000 shares and 35,000 shares of common stock, respectively. (2)                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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