4.	SHORT-TERM INVESTMENTS

Short-term investments of $65.0 million at December 31, 2014 and 2013 were comprised of U.S. Treasury Bills that mature through June 11, 2015. The interest rate on the U.S. Treasury Bills is less than one percent. The investments are classified as held-to-maturity and recorded at cost plus accrued interest. The fair value of the U.S. Treasury Bills at December 31, 2014 and 2013 approximated cost. For further discussion of fair value, refer to the fair value of financial instruments section of Note 1, Summary of Significant Accounting Policies.