diff --git a/idea/src/META-INF/plugin.xml b/idea/src/META-INF/plugin.xml
index 702cd766e88..63d44934ab2 100644
--- a/idea/src/META-INF/plugin.xml
+++ b/idea/src/META-INF/plugin.xml
@@ -137,6 +137,7 @@
       <extendWordSelectionHandler implementation="org.jetbrains.jet.plugin.editor.wordSelection.JetCodeBlockSelectioner"/>
       <extendWordSelectionHandler implementation="org.jetbrains.jet.plugin.editor.wordSelection.JetListSelectioner"/>
 
+      <lang.documentationProvider language="JAVA" implementationClass="org.jetbrains.jet.plugin.JetQuickDocumentationProvider" order="first"/>
       <documentationProvider implementation="org.jetbrains.jet.plugin.JetQuickDocumentationProvider"/>
       <configurationType implementation="org.jetbrains.jet.plugin.run.JetRunConfigurationType"/>
       <configurationType implementation="org.jetbrains.jet.plugin.k2jsrun.K2JSRunConfigurationType"/>
diff --git a/idea/src/org/jetbrains/jet/plugin/JetQuickDocumentationProvider.java b/idea/src/org/jetbrains/jet/plugin/JetQuickDocumentationProvider.java
index 4646441459c..44c7ca2d826 100644
--- a/idea/src/org/jetbrains/jet/plugin/JetQuickDocumentationProvider.java
+++ b/idea/src/org/jetbrains/jet/plugin/JetQuickDocumentationProvider.java
@@ -17,23 +17,29 @@
 package org.jetbrains.jet.plugin;
 
 import com.intellij.lang.documentation.AbstractDocumentationProvider;
+import com.intellij.lang.java.JavaDocumentationProvider;
+import com.intellij.psi.PsiClass;
 import com.intellij.psi.PsiElement;
+import com.intellij.psi.impl.compiled.ClsClassImpl;
+import com.intellij.psi.impl.compiled.ClsFileImpl;
 import com.intellij.psi.util.PsiTreeUtil;
+import com.intellij.xml.util.XmlStringUtil;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.lang.descriptors.DeclarationDescriptor;
 import org.jetbrains.jet.lang.psi.JetFile;
 import org.jetbrains.jet.lang.psi.JetReferenceExpression;
 import org.jetbrains.jet.lang.resolve.BindingContext;
 import org.jetbrains.jet.lang.resolve.BindingContextUtils;
+import org.jetbrains.jet.plugin.libraries.JetDecompiledData;
 import org.jetbrains.jet.plugin.project.WholeProjectAnalyzerFacade;
 import org.jetbrains.jet.resolve.DescriptorRenderer;
 
 /**
  * @author abreslav
+ * @author Evgeny Gerashchenko
  */
 public class JetQuickDocumentationProvider extends AbstractDocumentationProvider {
-
-    @Override
-    public String getQuickNavigateInfo(PsiElement element, PsiElement originalElement) {
+    private static String getText(PsiElement element, PsiElement originalElement, boolean mergeKotlinAndJava) {
         JetReferenceExpression ref;
         if (originalElement instanceof JetReferenceExpression) {
             ref = (JetReferenceExpression) originalElement;
@@ -46,35 +52,60 @@ public class JetQuickDocumentationProvider extends AbstractDocumentationProvider
                     .getBindingContext();
             DeclarationDescriptor declarationDescriptor = bindingContext.get(BindingContext.REFERENCE_TARGET, ref);
             if (declarationDescriptor != null) {
-                return render(declarationDescriptor);
+                return render(declarationDescriptor, bindingContext, element, originalElement, mergeKotlinAndJava);
             }
             PsiElement psiElement = BindingContextUtils.resolveToDeclarationPsiElement(bindingContext, ref);
             if (psiElement != null) {
                 declarationDescriptor = bindingContext.get(BindingContext.DECLARATION_TO_DESCRIPTOR, psiElement);
                 if (declarationDescriptor != null) {
-                    return render(declarationDescriptor);
+                    return render(declarationDescriptor, bindingContext, element, originalElement, mergeKotlinAndJava);
                 }
             }
             return "Unresolved";
         }
+        return null;
+    }
 
-//        if (originalElement.getNode().getElementType() == JetTokens.IDENTIFIER) {
-//            JetDeclaration declaration = PsiTreeUtil.getParentOfType(originalElement, JetDeclaration.class);
-//            BindingContext bindingContext = AnalyzingUtils.analyzeFileWithCache((JetFile) element.getContainingFile(), ErrorHandler.DO_NOTHING);
-//            DeclarationDescriptor declarationDescriptor = bindingContext.getDeclarationDescriptor(declaration);
-//            if (declarationDescriptor != null) {
-//                return render(declarationDescriptor);
-//            }
-//        }
-        return "Not a reference";
+    @Override
+    public String getQuickNavigateInfo(PsiElement element, PsiElement originalElement) {
+        return getText(element, originalElement, true);
     }
 
     @Override
     public String generateDoc(PsiElement element, PsiElement originalElement) {
-        return getQuickNavigateInfo(element, originalElement);
+        return getText(element, originalElement, false);
     }
 
-    private String render(DeclarationDescriptor declarationDescriptor) {
-        return DescriptorRenderer.HTML.render(declarationDescriptor);
+    private static String render(@NotNull DeclarationDescriptor declarationDescriptor, @NotNull BindingContext bindingContext,
+            PsiElement element, PsiElement originalElement, boolean mergeKotlinAndJava) {
+        String renderedDecl = DescriptorRenderer.HTML.render(declarationDescriptor);
+        if (isKotlinDeclaration(declarationDescriptor, bindingContext)) {
+            return renderedDecl;
+        } else {
+            if (mergeKotlinAndJava) {
+                return renderedDecl + "\nOriginal: " + XmlStringUtil.escapeString(
+                        new JavaDocumentationProvider().getQuickNavigateInfo(element, originalElement));
+            } else {
+                return null;
+            }
+        }
+    }
+
+    private static boolean isKotlinDeclaration(DeclarationDescriptor descriptor, BindingContext bindingContext) {
+        PsiElement declaration = BindingContextUtils.descriptorToDeclaration(bindingContext, descriptor);
+        if (declaration == null) return false;
+        if (JetLanguage.INSTANCE == declaration.getLanguage()) return true;
+        ClsClassImpl clsClass = PsiTreeUtil.getParentOfType(declaration, ClsClassImpl.class);
+        if (clsClass == null) return false;
+        PsiClass delegate = clsClass.getUserData(ClsClassImpl.DELEGATE_KEY);
+        if (delegate != null) {
+            if (delegate instanceof ClsClassImpl) {
+                clsClass = (ClsClassImpl) delegate;
+            }
+            else {
+                return false;
+            }
+        }
+        return JetDecompiledData.isKotlinFile((ClsFileImpl) clsClass.getContainingFile());
     }
 }