VT Fact Viewer
XHTML
VT Fact Viewer can only read files that are in XHTML format.
HMRC require that iXBRL files submitted to them are in XHTML format. Although the Inline XBRL standard does allow files to be in ordinary HTML format, these cannot be read by standard software components. It seems unlikely therefore that any program will produce iXBRL files that do not comply with the XHTML standard.