Editing an html file like xml file

Question

Hi,

I need to convert HTML file to iXBRL format. iXBRL format is basically html with some embedded nodes or some information of html file wrapped under ixbrl tags. For this, I will need to SEARCH and REMOVE some nodes from HTML file and WRAP some nodes under iXBRL tags.

I'm not able to use XML DOM as it shoots an exception on content type. .Net htmldocument class doesn't support removing the nodes and replacing them, neither I could see the Save option.

I tried using HTML Agility Pack but It can't find the nodes because of namespaces in the node name and it doesn't have any option to specify namespaces (line namespace manager in .net).

Can I specify namespace in XPATH expression? How?

Can anyone help me in Editing HTML (or XHTML) files using .net or any free library.