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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
	Mar. 31, 2021	Mar. 31, 2020
Percentage of NFIP claims ceded by federal government	100.00%
Ceded premiums written	$ (65,742)	$ (62,087)
Ceded premiums earned	(67,519)	(66,861)
Ceded loss and loss expenses incurred	$ (2,207)	$ (5,096)

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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