Financial Instruments (Schedule of AFS Unrealized Gain (Loss)) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Unrealized gross gains	$ 10.3	$ 0.8
Unrealized gross losses	4.0	29.0
Fair value of securities in an unrealized gain position	429.5	84.3
Fair value of securities in an unrealized loss position	$ 141.1	$ 858.6

Debt Securities, Available-for-sale, Unrealized Gain Position

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

+ References

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