c# - Use Regex to remove outer parentheses from nested expression, but leave inner parentheses? -

i'm working on figuring out regular expression take value such as:

transformer winding connections (wye (star) or delta) 

and match:

wye (star) or delta 

what have far is:

      string longname = "transformer winding connections (wye (star) or delta)";        // match until first parentheses       regex nameregex = new regex(@"([^(]*)");        match namematch = nameregex.match(longname);        // match first parentheses on           regex valueregex = new regex(@"\(.+\)");        match valuematch = valueregex.match(longname); 

valuematch returning:

(wye (star) or delta) 

is there clever way remove first set of parentheses in c#?

if want deal 1 level fine.

 @"\((?:\([^()]*\)|[^()])*\)" 

or

if don't want match outer paranthesis.

@"(?<=\()(?:\([^()]*\)|[^()])*(?=\))" 

demo