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Reinsurance (Ceded Premiums and Losses Related to Flood Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Ceded premiums written	$ (116,301)	$ (111,303)	$ (221,448)	$ (211,305)
Ceded premiums earned	(109,031)	(103,471)	(218,392)	(205,497)
Ceded loss and loss expenses incurred	(51,364)	(59,064)	$ (81,733)	(102,407)
National Flood Insurance Program [Member]
Percentage of NFIP claims ceded by federal government			100.00%
Ceded premiums written	(74,187)	(71,574)	$ (136,274)	(131,587)
Ceded premiums earned	(67,369)	(63,804)	(134,230)	(126,067)
Ceded loss and loss expenses incurred	$ (12,991)	$ (21,063)	$ (18,087)	$ (34,749)

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- 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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