Shareholders' Equity (Narrative) (Details) In Millions, except Share data, unless otherwise specified	1 Months Ended		12 Months Ended						12 Months Ended
	Aug. 31, 2011 USD ($)	Nov. 30, 2010 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2010 CHF	Dec. 31, 2009 CHF	Dec. 31, 2011 CHF	Dec. 31, 2009 USD ($)	Dec. 31, 2011 Common Stock Par Value [Member] CHF
Stockholders' Equity [Line Items]
Common shares - par value					30.57		30.27
Dividends declared per common share			$ 1.38	$ 1.30	1.31	1.26			1.22
Par value distribution per share							0.30	$ 1.19
Dividend installments			$ 0.35
The number of votes associated with one Common Share			1
The maximum ownership percentage for voting allowed for any one shareholder			10.00%
Revised dividend installments			$ 0.47
Common shares in treasury, shares			5,905,136	6,151,707	6,151,707			1,316,959
Stock repurchase program, authorized amount	$ 303	$ 600
Repurchase of outstanding common shares			2,058,860	4,926,082	4,926,082
Cost of shares acquired			132	303
Share repurchase authorization remains	$ 197		$ 468
Authorized share capital for general purposes			140,000,000
Conditional share capital for bonds and similar debt issuances			33,000,000
Par value per share of conditional share capital for bonds and similar debt instruments									30.27
Par value per share of conditional share capital for employee benefit plans									30.27
Conditional share capital for employee benefit plans			25,410,929