Short-term Investments
 12 Months Ended
Dec. 31, 2016
Short-term Investments [Abstract]  
Short-Term Investments
SHORT-TERM INVESTMENTS

Short-term marketable securities for the periods presented were comprised of the following (in thousands):
 
December 31, 2016
Security Type
Cost
 
Gross Unrealized Gains
 
Gross Unrealized Losses
 
Fair Value
U.S. government fixed income securities
$
19,403

 
$
40

 
$
—

 
$
19,443


Short-term investments at December 31, 2016 were comprised of investments in highly liquid, AAA, U.S. government fixed income securities with maturity dates in 2017. There were no short-term investments at December 31, 2015.

U.S. government fixed income securities. The Company has the ability to hold these securities until maturity, currently has no intent to sell, there is no requirement to sell and the Company believes that it can recover the amortized cost of these investments. The Company has found no evidence of impairment due to credit losses in its portfolio. However, the Company cannot provide any assurance that its portfolio of short-term marketable securities will not be impacted by adverse conditions in the financial markets, which may require the Company in the future to record an impairment charge for credit losses which could adversely impact its financial results.

For the year ended December 31, 2016, proceeds from the sale of short-term marketable securities classified as available-for-sale were $43,232,000 and gross realized gains were $1,000. For the year ended December 31, 2015, proceeds from the sale of short-term marketable securities were $82,115,000 and gross realized losses were $617,000. For the year ended December 31, 2014, proceeds from the sale of short-term marketable securities were $182,115,000 and gross realized losses were $2,188,000. Gross realized gains are recorded in the statements of operations in other income (expense).