Collateralized Reinsurance And Trust Agreements (Schedule of Proceeds from Issuance of Notes Held in Reinsurance Trusts) (Details) - Kilimanjaro Re Limited [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($)
Effects of Reinsurance [Line Items]
Amount	$ 2,325,000
Series 2017-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 13, 2017
Maturity Date	Apr. 13, 2022
Amount	$ 50,000
Series 2017-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 13, 2017
Maturity Date	Apr. 13, 2022
Amount	$ 75,000
Series 2017-1 Class C-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 13, 2017
Maturity Date	Apr. 13, 2022
Amount	$ 175,000
Series 2018-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 06, 2022
Amount	$ 62,500
Series 2018-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 06, 2022
Amount	$ 200,000
Series 2018-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 05, 2023
Amount	$ 62,500
Series 2018-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 05, 2023
Amount	$ 200,000
Series 2019-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2023
Amount	$ 150,000
Series 2019-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2023
Amount	$ 275,000
Series 2019-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2024
Amount	$ 150,000
Series 2019-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2024
Amount	$ 275,000
Series 2021-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 08, 2021
Maturity Date	Apr. 21, 2025
Amount	$ 150,000
Series 2021-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 08, 2021
Maturity Date	Apr. 21, 2025
Amount	$ 85,000
Series 2021-1 Class C-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 08, 2021
Maturity Date	Apr. 21, 2025
Amount	$ 85,000
Series 2021-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 08, 2021
Maturity Date	Apr. 20, 2026
Amount	$ 150,000
Series 2021-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 08, 2021
Maturity Date	Apr. 20, 2026
Amount	$ 90,000
Series 2021-1 Class C-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 08, 2021
Maturity Date	Apr. 20, 2026
Amount	$ 90,000