SQL & PL/SQL

Hello,

I have a quick question about XMLType and how to extract values from it... I have one with many namespaces like this one:

WITH T AS (
   SELECT 
'
   <project xmlns="http://www.test.com/xid/v2">
     <Node>NodeValue</Node>
     <Content>
       <Document:Document xmlns:Document="http://other.domain.be/prj/types/prj/file/1" xmlns="http://other.domain.be/prj/types/prj/file/1">
         <Details>
           <Id type="Local">123456</Id>
           <Id type="Remote">654321</Id>
         </Details>
       </Document:Document>
     </Content> 
   </project>
' x 
FROM dual  
)  
SELECT ExtractValue(XMLType(x), '/project/Node', 'xmlns="http://www.test.com/xid/v2"'), 
       ExtractValue(XMLType(x), '/project/Content/Document/Details/Id[@type="Local"]', 'xmlns="http://www.test.com/xid/v2"')
  FROM t;

And when I try to extract Local Id of a document, it always returns null. Any idea why? I'm using Oracle 11.2;

Thank you for your help.