Shareholders' Equity (Detail)	3 Months Ended				6 Months Ended					1 Months Ended	3 Months Ended	6 Months Ended	1 Months Ended
	Jun. 30, 2014 USD ($)	Jun. 30, 2014 CHF	Jun. 30, 2013 USD ($)	Jun. 30, 2013 CHF	Jun. 30, 2014 USD ($)	Jun. 30, 2014 CHF	Jun. 30, 2013 USD ($)	Jun. 30, 2013 CHF	Dec. 31, 2013 CHF	Nov. 30, 2013 November 2013 Stock Repurchase Plan [Member] USD ($)	Jun. 30, 2014 November 2013 Stock Repurchase Plan [Member] USD ($)	Jun. 30, 2014 November 2013 Stock Repurchase Plan [Member] USD ($)	Jul. 29, 2014 November 2013 Stock Repurchase Plan [Member] Subsequent Event [Member] USD ($)
Equity, Class of Treasury Stock [Line Items]
Share repurchase amount											$ 237,000,000	$ 569,000,000	$ 133,000,000
Repurchase of outstanding common shares, shares											2,306,000	5,793,882	1,281,630
Share repurchase authorization remains												1,370,000,000	1,240,000,000
Common Shares in treasury, shares	6,606,823	6,606,823			6,606,823	6,606,823			3,038,477
Stock repurchase program, authorized amount										$ 2,000,000,000
Increase to dividend approved by shareholders in January					$ 0.12
Dividends declared per common share	$ 0.65	0.58	$ 0.51	0.48	$ 1.40	1.23	$ 1.00	0.94
Par Value Reduction					$ 0.51
Common Shares, par value		26.01				26.01			27.04