Basis of Presentation (Details) Accumulated Other Comprehensive Income (USD $)	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax
Net unrealized appreciation on available-for-sale investments	$ 5,998,000	$ 5,998,000		$ 4,455,000
Foreign currency translation	(6,512,000)	(6,512,000)		(6,469,000)
Accumulated other comprehensive loss	(514,000)	(514,000)		(2,014,000)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	(426,000)	(830,000)	(493,000)
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax	406,000	547,000	276,000
Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax
Deferred tax liability on other comprehensive income	3,300,000	3,300,000		2,400,000
Accumulated Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax
Deferred income tax asset on other comprehensive loss	$ 3,300,000	$ 3,300,000		$ 3,300,000