This paper presents a new adaptive approach for document image binarization. The proposed method is mainly based on the combination of several state- of-the-art binarization methodologies as well as on the efficient incorporation of the edge information of the gray scale source image. An enhancement step based on mathematical morphology operations is also involved in order to produce a high quality result while preserving stroke information. The proposed method demonstrated superior performance against six (6) well-known techniques on numerous degraded handwritten and machine- printed documents. The performance evaluation is based on visual criteria as well as on an objective evaluation methodology.