SHORT-TERM INVESTMENTS

3 Months Ended

Mar. 31, 2016

Investments Schedule [Abstract]

SHORT-TERM INVESTMENTS

SHORT-TERM INVESTMENTS

Prior to December 31, 2014, the Company invested its excess cash in high quality (AAA-rated) short-maturity marketable debt securities, such as commercial paper and corporate bonds. The Company historically held all of its investments in marketable debt securities until maturity. Accordingly, these investments were accounted for as “held-to-maturity” securities and were recorded at amortized cost, which approximated fair value. During the first quarter of 2015, the Company allowed all of its investments in marketable debt securities to mature. The proceeds from these maturities of $200.1 million were used to fund the Tower acquisition on March 9, 2015. The Company held no short-term investments as of March 31, 2016 and December 31, 2015.