v3.2.0.727

Shareholders' equity Shareholders' equity (Details) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2015 USD ($) $ / shares shares | Jun. 30, 2015 USD ($) SFr / shares shares | Jun. 30, 2014 USD ($) $ / shares shares | Jun. 30, 2014 USD ($) SFr / shares | Jun. 30, 2015 USD ($) $ / shares shares | Jun. 30, 2015 USD ($) SFr / shares shares | Jun. 30, 2014 USD ($) $ / shares shares | Jun. 30, 2014 USD ($) SFr / shares | Jun. 30, 2013 $ / shares | Jun. 30, 2015 SFr / shares | May. 31, 2015 $ / shares | Jan. 01, 2015 USD ($) | Dec. 31, 2014 SFr / shares shares | May. 31, 2014 $ / shares | Nov. 30, 2013 USD ($) | May. 31, 2013 $ / shares
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares in treasury, shares | shares | 19,018,131 | 19,018,131 |  |  | 19,018,131 | 19,018,131 |  |  |  |  |  |  | 14,172,726 |  |  |
Par Value Reduction | (per share) | $ 0 | SFr 0 | $ 0.65 | SFr 0.58 | $ 0.65 | SFr 0.62 | $ 1.16 | SFr 1.03 |  |  |  |  |  |  |  |
Dividends Declared From Additional Paid In Capital | (per share) | 0.67 | 0.62 | 0.00 | 0 | 0.67 | 0.62 | 0.24 | 0.20 |  |  |  |  |  |  |  |
Annual dividend per share approved by shareholders | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 2.68 |  |  | $ 2.60 |  | $ 2.04
Increase to dividend approved by shareholders in January | $ / shares |  |  |  |  |  |  | 0.12 |  |  |  |  |  |  |  |  |
Dividends declared per common share | (per share) | 0.67 | SFr 0.62 | $ 0.65 | SFr 0.58 | 1.32 | SFr 1.24 | 1.40 | SFr 1.23 |  |  |  |  |  |  |  |
Common Stock, Dividend Rate, Per-Dollar-Amount | $ / shares | $ 0.65 |  |  |  | $ 0.67 |  |  |  | $ 0.51 |  |  |  |  |  |  |
Common Stock, Dividend Rate, Per-Dollar-Amount After Increase | $ / shares |  |  |  |  |  |  | $ 0.63 |  |  |  |  |  |  |  |  |
Common Shares, par value | SFr / shares |  |  |  |  |  |  |  |  |  | SFr 24.15 |  |  | SFr 24.77 |  |  |
2015 Stock Repurchase Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares repurchased | $ 394 |  |  |  | $ 734 |  |  |  |  |  |  |  |  |  |  |
Repurchase of outstanding common shares, shares | shares | 3,650,200 |  |  |  | 6,677,663 |  |  |  |  |  |  |  |  |  |  |
Share repurchase authorization remains | $ 766 | SFr 766 |  |  | $ 766 | SFr 766 |  |  |  |  |  |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  |  |  |  |  |  |  |  | $ 1,500 |  |  |  |
November 2013 Stock Repurchase Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares repurchased |  |  | $ 237 |  |  |  | $ 569 |  |  |  |  |  |  |  |  |
Repurchase of outstanding common shares, shares | shares |  |  | 2,306,000 |  |  |  | 5,793,882 |  |  |  |  |  |  |  |  |
Share repurchase authorization remains |  |  | $ 1,374 | SFr 1,374 |  |  | $ 1,374 | SFr 1,374 |  |  |  |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,000 |

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