Investments (Investments Classified by Contractual Maturity Date) (Details) - Fixed Income Securities	Sep. 30, 2019 USD ($)
Debt Securities, Available-for-sale [Line Items]
Due within one year	$ 206,184,561
Due between one and five years	59,332,380
Due over five years	35,093,088
Total	$ 300,610,029

Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Years, Fair Value

No definition available.

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- Definition

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 second through fifth 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.

+ References

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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