diff --git a/vtkPolyDataBooleanFilter.cxx b/vtkPolyDataBooleanFilter.cxx
index c5a082e..e6e3cb8 100644
--- a/vtkPolyDataBooleanFilter.cxx
+++ b/vtkPolyDataBooleanFilter.cxx
@@ -1159,7 +1159,7 @@ bool vtkPolyDataBooleanFilter::CutCells (vtkPolyData *pd, PolyStripsType &polySt
 
         strips.erase(std::remove_if(strips.begin(), strips.end(), fct), strips.end());
 
-        std::map<vtkIdType, std::reference_wrapper<StripType>> stripsM;
+        std::map<std::size_t, std::reference_wrapper<StripType>> stripsM;
 
         for (auto &strip : strips) {
             stripsM.emplace(strip.front().strip, strip);