SCHEDULE IV-REINSURANCE (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
SCHEDULE IV-REINSURANCE [Abstract]
Gross amount	$ 1,065,663	$ 1,170,868	$ 1,236,949
Ceded to other companies	34,918	50,924	71,293
Assumed from other companies	2,425	3,891	3,091
Net amount	$ 1,033,170	$ 1,123,835	$ 1,168,747
Percentage of amount assumed to net	0.20%	0.30%	0.30%