Statutory (Unaudited) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statutory Accounting Practices [Abstract]
Net income (loss) of the insurance subsidiaries in accordance with statutory accounting practices	$ 29,262	$ (19,120)	$ 12,542
Consolidated statutory surplus for subsidiaries	338,857	313,705
Amount of statutory surplus transferred by dividend or loan to the parent company	55,192
Additional shareholders' equity of insurance subsidiaries that could be advanced or loaned to parent company with prior notification and approval from regulatory authorities	196,234
Minimum statutory surplus necessary for the insurance subsidiaries to satisfy statutory risk based capital requirements	$ 86,060