Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Sales \| Debt Securities \| Available for sale securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	$ 43,041	$ 68,621
Gross Realized Gains	1,476	4,959
Gross Realized Losses	(107)	(1,518)
Net Realized Gain (Loss)	1,369	3,441
Sales \| Equity Securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	157,973	66,185
Gross Realized Gains	52,409	22,172
Gross Realized Losses	(1,787)	(8,756)
Net Realized Gain (Loss)	50,622	13,416
Calls/Maturities \| Debt Securities \| Available for sale securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	296,563	199,036
Gross Realized Gains	471	525
Gross Realized Losses	(109)	(10)
Net Realized Gain (Loss)	$ 362	$ 515

The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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The difference between the carrying value and the sale price of an investment. A loss would be recognized when the sale price of the investment is less than the carrying value of the investment. This element refers to the Loss included in earnings and not to the cash proceeds of the sale.

+ References

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-Topic 220
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Amount of realized gain (loss) on investment in marketable security, excluding other-than-temporary impairment (OTTI).

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The cash inflow associated with the sale, maturity and collection of all investments such as debt, security and so forth during the period.

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