Fair Value Measurements (Carrying Amounts And Fair Values Of Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Assets:
Available-for-sale securities	$ 342.3	$ 257.5
Carrying Amount
Assets:
Available-for-sale securities	342.3	257.5
Liabilities:
Short-term borrowings	845.2	71.9
Long-term borrowings	12,025.2	3,401.5
Fair Value
Assets:
Available-for-sale securities	342.3	257.5
Liabilities:
Short-term borrowings	845.2	71.9
Long-term borrowings	$ 12,471.4	$ 3,809.1