Long Term Restricted Investments

Restricted investments relate to reimbursement obligations under letters of credit issued for the benefit of lessors of our office space.  As of March 31, 2015 and December 31, 2014, our Long-term restricted investments were $9,888 and $5,922, respectively.  During the three months ended March 31, 2015, we increased our letters of credit by $3,966 associated with leased office space.