Investments in Securities and Fair Value Investments in Securities (Schedule of Unrealized Losses on Investments) (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	(9)	(12)
Special revenue issuer obligations of U.S. states, territories and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,102	1,103
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(2)	(3)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,102	1,103
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(2)	(3)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	8,493	20,630
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(13)	(24)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	6,203	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(35)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	14,696	20,630
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(48)	(24)
Total fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	8,493	20,630
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(13)	(24)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	7,305	1,103
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(37)	(3)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	15,798	21,733
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (50)	$ (27)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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