INVESTMENTS (Details 2) $ in Millions	Jun. 30, 2015 USD ($)
Available-for-sale securities by contractual maturity
Due within one year, Cost	$ 503.7
Due after one through five years, Cost	414.3
Cost, Total	918.0
Due within one year, Fair Value	503.7
Due after one through five years, Fair Value	414.1
Fair Value, Total	$ 917.8