v2.4.0.8

Shareholders' equity Shareholders' equity (Details) | 3 Months Ended | 9 Months Ended |  |  |  | 3 Months Ended | 9 Months Ended |  | 1 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2014 USD ($) | Sep. 30, 2014 CHF | Sep. 30, 2013 USD ($) | Sep. 30, 2013 CHF | Sep. 30, 2014 USD ($) | Sep. 30, 2014 CHF | Sep. 30, 2013 USD ($) | Sep. 30, 2013 CHF | May 31, 2014 USD ($) | Dec. 31, 2013 CHF | May 31, 2013 USD ($) | Sep. 30, 2014 November 2013 Stock Repurchase Plan [Member] USD ($) | Sep. 30, 2014 November 2013 Stock Repurchase Plan [Member] USD ($) | Nov. 30, 2013 November 2013 Stock Repurchase Plan [Member] USD ($) | Oct. 28, 2014 November 2013 Stock Repurchase Plan [Member] Subsequent Event [Member] USD ($)
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share repurchase amount |  |  |  |  |  |  |  |  |  |  |  | $ 450,000,000 | $ 1,019,000,000 |  | $ 74,000,000
Repurchase of outstanding common shares, shares |  |  |  |  |  |  |  |  |  |  |  | 4,349,302 | 10,143,184 |  | 699,965
Share repurchase authorization remains |  |  |  |  |  |  |  |  |  |  |  | 924,000,000 | 924,000,000 |  | 850,000,000
Common Shares in treasury, shares | 10,720,855 | 10,720,855 |  |  | 10,720,855 | 10,720,855 |  |  |  | 3,038,477 |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,000,000,000 |
Annual dividend per share approved by shareholders |  |  |  |  |  |  |  |  | $ 2.60 |  | $ 2.04 |  |  |  |
Dividends Declared From Additional Paid In Capital |  |  |  |  | $ 0.24 | 0.20 |  |  |  |  |  |  |  |  |
Increase to dividend approved by shareholders in January |  |  |  |  | $ 0.12 |  |  |  |  |  |  |  |  |  |
Dividends declared per common share |  |  |  |  | $ 2.05 | 1.84 |  |  |  |  |  |  |  |  |
Par Value Reduction | $ 0.65 | 0.61 | $ 0.51 | 0.46 | $ 1.81 | 1.64 | $ 1.51 | 1.40 |  |  |  |  |  |  |
Common Shares, par value |  | 25.40 |  |  |  | 25.40 |  |  |  | 27.04 |  |  |  |  |

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