Investments - Schedule of Other Investments (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Other Investments
Other investments, cost	$ 25,893
Total other investments	27,651
Certificates of Deposit
Other Investments
Other investments, cost	300
Unrealized Loss	0
Unrealized Gain	0
Fair value - certificates of deposit	300
Limited Partnership
Other Investments
Other investments, cost	17,471
Unrealized Loss	60
Unrealized Gain	1,822
Fair value - partnerships	19,233
Short-term Investments
Other Investments
Other investments, cost	8,122
Unrealized Loss	4
Unrealized Gain	0
Fair Value - short term investments	8,118
Other Investments
Other Investments
Unrealized Loss	64
Unrealized Gain	$ 1,822

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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