Letters of Credit

12 Months Ended

Dec. 31, 2014

Financial Instruments Pledged as Collateral [Abstract]

Letters of Credit

Letters of Credit

In connection with agreements with certain airports, the Company is required to post letters of credit, which totaled $0.2 million as of both December 31, 2014 and 2013. The issuing banks require the Company deposit funds at those banks to cover the amounts that could be drawn under the letters of credit. These funds are generally invested in money market accounts and are classified as long-term assets within other long-term assets. Additionally, as of December 31, 2014, the Company had a $25.1 million unsecured standby letter of credit facility, of which $10.3 million had been drawn upon for issued letters of credit to airports and insurance underwriters.