Investments	12 Months Ended
Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	NOTE 3 – INVESTMENTS Cash and cash equivalents includes investments in money market funds that are valued based on the net asset value of the funds. The cash equivalents consist primarily of money market funds that are Level 1 measurements. The investments in these funds were $55.6 million as of December 31, 2017. We had no such investments as of December 31, 2016. All other investments are classified as held-to-maturity and consist of highly liquid instruments including primarily corporate bonds and commercial paper. As of December 31, 2017, the amortized cost of these investments equaled the net carrying value, which was $30.1 million. We had no such investments as of December 31, 2016. All held-to-maturity securities as of December 31, 2017 mature in one year or less. See Note 8, Fair Value Measurements, for additional information.

Investments

12 Months Ended

Dec. 31, 2017

Investments, Debt and Equity Securities [Abstract]

NOTE 3 – INVESTMENTS

Cash and cash equivalents includes investments in money market funds that are valued based on the net asset value of the funds. The cash equivalents consist primarily of money market funds that are Level 1 measurements. The investments in these funds were $55.6 million as of December 31, 2017. We had no such investments as of December 31, 2016.

All other investments are classified as held-to-maturity and consist of highly liquid instruments including primarily corporate bonds and commercial paper. As of December 31, 2017, the amortized cost of these investments equaled the net carrying value, which was $30.1 million. We had no such investments as of December 31, 2016. All held-to-maturity securities as of December 31, 2017 mature in one year or less. See Note 8, Fair Value Measurements, for additional information.