This paper describes the Integrated Domain Modeling approach and introduces the supporting toolset as a solution to the complex domain-modeling task. This approach integrates artificial intelligence (AI) and system analysis by exploiting ontology, natural language processing (NLP), use cases and model-driven architecture (MDA) for knowledge engineering and domain modeling. The IDM toolset provides the opportunity to automatically generate the initial AS-IS model from the formally defined domain knowledge. In this paper, we describe in detail the scope, architecture and implementation of the toolset.