Comprehensive Income (Details 1) (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Balance, Beginning of Period	$ 907,415
Change in component during the period	157,273
Balance, End of Period	1,064,688
Accumulated Currency Translation Adjustments Member
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Balance, Beginning of Period	270,526
Change in component during the period	41,127
Balance, End of Period	311,653
Unrealized Appreciation Of Securities Member
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Balance, Beginning of Period	651,449
Change in component during the period	115,574
Balance, End of Period	767,023
Pension And Postretirement Benefits Member
Accumulated Other Comprehensive Income Loss Net Of Tax [Line Items]
Balance, Beginning of Period	(14,560)
Change in component during the period	572
Balance, End of Period	$ (13,988)