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Segment Reporting Disclosures (Summary of Top Five Independent Brokers Concentration) (Details) - Top Five Independent Brokers	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Insurance [Member]
Summary of Top Five Independent Brokers Concentration [Line Items]
Percentage of gross premiums written	33.00%	34.00%	32.00%
Reinsurance [Member]
Summary of Top Five Independent Brokers Concentration [Line Items]
Percentage of gross premiums written	95.00%	99.00%	90.00%
Underwriting Operations [Member]
Summary of Top Five Independent Brokers Concentration [Line Items]
Percentage of gross premiums written	37.00%	40.00%	38.00%

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Summary of Top Five Independent Brokers Concentration [Line Items]

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