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Reinsurance (Ceded Premiums and Losses Related to Flood Operations) (Details) - National Flood Insurance Program [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Percentage of NFIP claims ceded by federal government			100.00%
Ceded premiums written	$ (77,697)	$ (77,318)	$ (218,520)	$ (213,592)
Ceded premiums earned	(69,197)	(68,427)	(203,549)	(202,656)
Ceded loss and loss expenses incurred	$ (153,713)	$ (48,132)	$ (174,861)	$ (66,219)

X

- Definition

Percentage of unpaid NFIP claims ceded to federal government.

+ References

No definition available.

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Amount of earned premiums ceded to other entities.

+ References

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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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