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Reinsurance (Ceded Premiums and Losses Related to Flood Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Ceded premiums written	$ (105,147)	$ (100,002)
Ceded premiums earned	(109,362)	(102,026)
Ceded loss and loss expenses incurred	$ (30,369)	(43,343)
National Flood Insurance Program [Member]
Percentage of NFIP claims ceded by federal government	100.00%
Ceded premiums written	$ (62,087)	(60,013)
Ceded premiums earned	(66,861)	(62,263)
Ceded loss and loss expenses incurred	$ (5,096)	$ (13,686)

X

- Definition

Percentage of unpaid NFIP claims ceded to federal government.

+ References

No definition available.

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- 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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