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Reinsurance (Ceded Premiums and Losses Related to Flood Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Percentage of NFIP claims ceded to the federal government	100.00%
Ceded premiums written	$ (527,248)	$ (489,488)	$ (455,708)
Ceded premiums earned	(537,884)	(477,012)	(451,883)
Ceded loss and loss expense	(449,020)	(296,341)	(203,412)
National Flood Insurance Program [Member]
Ceded premiums written	(259,246)	(284,311)	(274,042)
Ceded premiums earned	(274,100)	(274,384)	(271,598)
Ceded loss and loss expense	$ (200,467)	$ (215,224)	$ (78,993)

X

- Definition

Percentage of unpaid NFIP flood premium, losses and loss expense claims ceded by federal government.

+ References

No definition available.

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X

- Definition

Amount of earned premiums ceded to other entities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
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Amount of written premiums ceded to other entities.

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Amount of reduction of provision for policy benefits and costs incurred for policies ceded.

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