1. A method executed on a computing device to detect a document type of a document, the method comprising: analyzing the document to detect features of the document and pages of the document based on an action selecting the document; detecting separative features as a subset of the features; identifying one of the separative features as a reading order complexity associated with the pages; generating a reading order tree for each of the pages to compute a value for the reading order complexity; computing the value for the reading order complexity by adding a number of roots in the reading order tree with a sum of incoming connections for each element of the reading order tree multiplied by outgoing connections for each element; detecting a type of the pages based on the features; and aggregating the type of the pages and values of the features of the document to identify the document type of the document.