OPENOLAT-157: made order-total information in the detail view consistent with the summary table

src/main/java/org/olat/resource/accesscontrol/ui/OrderDetailController.java

@@ -111,7 +111,12 @@ public class OrderDetailController extends FormBasicController {
 		String creationDateStr = Formatter.getInstance(getLocale()).formatDateAndTime(creationDate);
 		uifactory.addStaticTextElement("creation-date", "order.creationDate", creationDateStr, mainLayout);
 		
-		String orderTotal = PriceFormat.fullFormat(order.getTotal());
+		String orderTotal;
+		if (order.getTotal().getAmount().signum() != 0) {
+			orderTotal = PriceFormat.fullFormat(order.getTotal());
+		} else {
+			orderTotal = "-";
+		}
 		String orderTotalStr;
 		if(acModule.isVatEnabled()) {
 			BigDecimal vat = acModule.getVat();