Ameritrade ( AMTD - Get Report) said Chief Operating Officer Pete Ricketts is leaving the company to explore another opportunity, but he will continue to serve as vice chairman and a member of the board.

While chief operating officer, Ricketts was responsible for Ameritrade's retail client business, as well as clearing and marketing operations. As a result of Thursday's announcement, the Omaha, Neb., online broker said there will be some reorganization and other changes regarding reporting functions.

The company might also make adjustments to its integration planning in connection with the proposed acquisition of TD Waterhouse U.S.A..

Shares of Ameritrade closed at $19.70, down 30 cents.