Reinsurance Ceded - Additional Information (Detail) - Reinsurance Segment	6 Months Ended
	Jun. 30, 2022
Effects Of Reinsurance [Line Items]
Retrocession protection term	1 year
Minimum
Effects Of Reinsurance [Line Items]
Term of catastrophe bonds	3 years
Maximum
Effects Of Reinsurance [Line Items]
Term of catastrophe bonds	4 years