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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		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Percentage of NFIP claims ceded by federal government			100.00%
Ceded premiums written	$ (75,081)	$ (74,187)	$ (140,823)	$ (136,274)
Ceded premiums earned	(66,833)	(67,369)	(134,352)	(134,230)
Ceded loss and loss expenses incurred	$ (18,941)	$ (12,991)	$ (21,148)	$ (18,087)

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- Definition

Percentage of unpaid NFIP claims ceded to federal government.

+ References

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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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