int outlineLevel = columnInfo.getOutlineLevel();
boolean nestedGroup = false;
for (int i = startIdx; i <= endIdx; i++) {
CTCol ci = cols.getColArray(i);
if (outlineLevel == ci.getOutlineLevel()) {
ci.unsetHidden();
if (nestedGroup) {
nestedGroup = false;
ci.setCollapsed(true);
}
} else {