Shareholders' Equity (Share Capital Issued) (Details) In Thousands, except Share data	6 Months Ended
	Jun. 30, 2011 USD ($)	Jun. 30, 2011 CHF	Dec. 31, 2010 USD ($)	Dec. 31, 2010 CHF
Earnings Per Share
Share capital at end of period	$ 600,055		$ 600,055
Total shares issued at beginning of period	40,003,642
Total shares issued at end of period	40,003,642
Treasury shares issued, balance at beginning of period	1,914,416
Shares repurchased	969,163
Shares issued out of treasury	(824,980)
Total treasury shares at end of period	2,058,599
Total shares outstanding at end of period	37,945,043		38,089,226	38,089,226
Common shares, par value		15.00		15