Other Investments (Schedule of Maturities of Investments in Debt Securities) (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Other Investments [Abstract]
Amortized Cost, Due in one year or less	$ 15,154
Amortized Cost, Due after one through five years	27,172
Amortized Cost, Due after five through ten years
Amortized Cost, Due after ten years
Amortized Cost	42,326
Fair Value, Due in one year or less	15,154
Fair Value, Due after one through five years	28,742
Fair Value, Due after five through ten years
Fair Value, Due after ten years
Fair Value	$ 43,896

Amortized cost 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 fiscal year 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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