Financial Instruments (Contractual Maturities) (Details) $ in Millions	Jun. 30, 2019 USD ($)
Debt Securities Contractual Maturities
Total	$ 698.3
Less Than 1 Year	76.3
1-5 Years	447.1
6-10 Years	61.4
More Than 10 Years	$ 113.5

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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).

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