SCHEDULE IV-REINSURANCE (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
SCHEDULE IV-REINSURANCE [Abstract]
Gross amount	$ 1,170,868	$ 1,236,949	$ 1,406,977
Ceded to other companies	50,924	71,293	107,975
Assumed from other companies	3,891	3,091	3,339
Net amount	$ 1,123,835	$ 1,168,747	$ 1,302,341
Percentage of amount assumed to net	0.30%	0.30%	0.30%