Hi Michael,
I created the following XQuery function,

declare namespace xbrldi="http://xbrl.org/2006/xbrldi";
declare function mf:output-explicitMember( $dimName, $dimValue ) as element(){
    <xbrldi:explicitMember dimension="{$dimName}">
        namespace {prefix-from-QName($dimName)} {namespace-uri-from-QName($dimName)},
        namespace {prefix-from-QName($dimValue)} {namespace-uri-from-QName($dimValue)},

It raised an error message as:

Error on line 510 column 9
  XPST0003: XQuery syntax error in #... namespace {prefix-from-QName#:
    Namespace node constructors are not allowed in XQuery 1.0

Do you have any suggestions?

Thanks and best regards