Shares of Credit Suisse are rising in Tuesday trading on news that the Swiss bank is replacing its chief executive Brady Dougan with the head of British insurer Prudential, Tidjane Thiam. Dougan will step down at the end of June after eight years at Credit Suisse's helm. He led the bank through the 2008 financial crisis, but also failed to prevent it from paying billions in fines for aiding foreign clients in tax evasion. Thiam is credited with helping Prudential expand into emerging markets in recent years. The bank's chairman Urs Rohner cited Thiam's extensive international experience in wealth and asset management and in the successful development of new markets, which he said provides a firm foundation for leading Credit Suisse.