Reserves For Losses And LAE (Summary Of Incurred Losses With Respect To A&E Reserves On Both Gross And Net Of Reinsurance Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reserves For Losses And LAE [Abstract]
Gross basis: Beginning of period reserves	$ 476,205	$ 402,461	$ 442,821
Gross basis: Incurred losses	40,000	142,233	5,598
Gross basis: Paid losses	(83,088)	(68,490)	(45,958)
Gross basis: End of period reserves	433,117	476,205	402,461
Net basis: Beginning of period reserves	304,286	269,370	305,469
Net basis: Incurred losses	30,879	87,362	3,965
Net basis: Paid losses	(58,625)	(52,446)	(40,064)
Net basis: End of period reserves	$ 276,540	$ 304,286	$ 269,370