Goodwill and Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Goodwill And Intangible Assets [Line Items]
Goodwill	$ 268,376	$ 268,376	$ 268,376	[1]
Indefinite lived intangible assets, net carrying value	23,920	23,920	23,920
Finite lived intangible assets:
Gross carrying value	41,334	41,334	41,334	[2]
Accumulated amortization	(13,889)	(11,356)	(8,378)
Net carrying value	27,445	29,978	32,956
Amortization of intangible assets	(2,533)	(2,978)
Accumulated impairment losses:
Accumulated impairment loss, goodwill	156
Accumulated impairment loss, intangible assets	6,866
U S Insurance [Member]
Schedule Of Goodwill And Intangible Assets [Line Items]
Goodwill	$ 264,615

[1] Net of accumulated impairment charges of $156 that occurred prior to January 1, 2011.

[2] Net of accumulated impairment charges of $6,866 that occurred prior to January 1, 2011.