diff --git a/python/src/com/jetbrains/python/documentation/PythonDocumentationProvider.java b/python/src/com/jetbrains/python/documentation/PythonDocumentationProvider.java
index 2e6d4058ff76..6ee637fe6f10 100644
--- a/python/src/com/jetbrains/python/documentation/PythonDocumentationProvider.java
+++ b/python/src/com/jetbrains/python/documentation/PythonDocumentationProvider.java
@@ -100,8 +100,8 @@ public class PythonDocumentationProvider extends AbstractDocumentationProvider i
 
       return describeDecorators(cls, LSame2, ", ", LSame1).add(describeClass(cls, LSame2, false, false)).toString() + "\n" + summary;
     }
-    else if (element instanceof PyTargetExpression || element instanceof PyNamedParameter) {
-      return describeExpression((PyExpression)element);
+    else if (element instanceof PyExpression) {
+      return describeExpression((PyExpression)element, originalElement);
     }
     return null;
   }
@@ -131,7 +131,7 @@ public class PythonDocumentationProvider extends AbstractDocumentationProvider i
   }
 
   @Nullable
-  private static String describeExpression(PyExpression expr) {
+  private static String describeExpression(@NotNull PyExpression expr, @NotNull PsiElement originalElement) {
     final String name = expr.getName();
     if (name != null) {
       StringBuilder result = new StringBuilder((expr instanceof PyNamedParameter) ? "parameter" : "variable");
@@ -143,15 +143,17 @@ public class PythonDocumentationProvider extends AbstractDocumentationProvider i
           result.append(String.format(" \"%s\"", function.getName()));
         }
       }
-      result.append("\n").append(describeExpressionType(expr));
+      if (originalElement instanceof PyTypedElement) {
+        result.append("\n").append(describeType((PyTypedElement)originalElement));
+      }
       return result.toString();
     }
     return null;
   }
 
-  static String describeExpressionType(PyExpression expr) {
-    final TypeEvalContext context = TypeEvalContext.userInitiated(expr.getContainingFile());
-    return String.format("Inferred type: %s", getTypeName(context.getType(expr), context));
+  static String describeType(@NotNull PyTypedElement element) {
+    final TypeEvalContext context = TypeEvalContext.userInitiated(element.getContainingFile());
+    return String.format("Inferred type: %s", getTypeName(context.getType(element), context));
   }
 
   public static String getTypeDescription(@NotNull PyFunction fun) {
diff --git a/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java b/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
index 378ab8a676cc..c61693c075d7 100644
--- a/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
@@ -400,23 +400,26 @@ public class PyFunctionImpl extends PyPresentableElementImpl<PyFunctionStub> imp
 
   @Nullable
   private String extractReturnType() {
+    final String ARROW = "->";
+    final StructuredDocString structuredDocString = getStructuredDocString();
+    if (structuredDocString != null) {
+      return structuredDocString.getReturnType();
+    }
     final String docString = getDocStringValue();
-    if (docString == null) {
-      return null;
-    }
-    final List<String> lines = StringUtil.split(docString, "\n");
-    while (lines.size() > 0 && lines.get(0).trim().length() == 0) {
-      lines.remove(0);
-    }
-    if (lines.size() > 1 && lines.get(1).trim().length() == 0) {
-      String firstLine = lines.get(0);
-      int pos = firstLine.lastIndexOf("->");
-      if (pos >= 0) {
-        return firstLine.substring(pos + 2).trim();
+    if (docString != null && docString.contains(ARROW)) {
+      final List<String> lines = StringUtil.split(docString, "\n");
+      while (lines.size() > 0 && lines.get(0).trim().length() == 0) {
+        lines.remove(0);
+      }
+      if (lines.size() > 1 && lines.get(1).trim().length() == 0) {
+        String firstLine = lines.get(0);
+        int pos = firstLine.lastIndexOf(ARROW);
+        if (pos >= 0) {
+          return firstLine.substring(pos + 2).trim();
+        }
       }
     }
-    final StructuredDocString structuredDocString = getStructuredDocString();
-    return structuredDocString != null ? structuredDocString.getReturnType() : null;
+    return null;
   }
 
   private static class ReturnVisitor extends PyRecursiveElementVisitor {
diff --git a/python/testData/quickdoc/HoverOverControlFlowUnion.html b/python/testData/quickdoc/HoverOverControlFlowUnion.html
new file mode 100644
index 000000000000..056d6ba8ce3c
--- /dev/null
+++ b/python/testData/quickdoc/HoverOverControlFlowUnion.html
@@ -0,0 +1,2 @@
+variable "x"
+Inferred type: one of (str, int)
diff --git a/python/testData/quickdoc/HoverOverControlFlowUnion.py b/python/testData/quickdoc/HoverOverControlFlowUnion.py
new file mode 100644
index 000000000000..74ceb505df1b
--- /dev/null
+++ b/python/testData/quickdoc/HoverOverControlFlowUnion.py
@@ -0,0 +1,6 @@
+def foo(c):
+    if c:
+        x = 'foo'
+    else:
+        x = 1
+    return <the_ref>x
\ No newline at end of file
diff --git a/python/testSrc/com/jetbrains/python/PyQuickDocTest.java b/python/testSrc/com/jetbrains/python/PyQuickDocTest.java
index 5227fc4c0521..de9ea7ff9c04 100644
--- a/python/testSrc/com/jetbrains/python/PyQuickDocTest.java
+++ b/python/testSrc/com/jetbrains/python/PyQuickDocTest.java
@@ -216,4 +216,8 @@ public class PyQuickDocTest extends LightMarkedTestCase {
   public void testHoverOverParameter() {
     checkHover();
   }
+
+  public void testHoverOverControlFlowUnion() {
+    checkHover();
+  }
 }
diff --git a/python/testSrc/com/jetbrains/python/PyTypeTest.java b/python/testSrc/com/jetbrains/python/PyTypeTest.java
index 3daeb4fd9c57..2348a1039500 100644
--- a/python/testSrc/com/jetbrains/python/PyTypeTest.java
+++ b/python/testSrc/com/jetbrains/python/PyTypeTest.java
@@ -629,6 +629,17 @@ public class PyTypeTest extends PyTestCase {
     assertTrue(PyTypeChecker.isUnknown(type));
   }
 
+  public void testParameterOfFunctionTypeAndReturnValue() {
+    doTest("int",
+           "def func(f):\n" +
+           "    '''\n" +
+           "    :type f: (unknown) -> str\n" +
+           "    '''\n" +
+           "    return 1\n" +
+           "\n" +
+           "expr = func(foo)\n");
+  }
+
   private static TypeEvalContext getTypeEvalContext(@NotNull PyExpression element) {
     return TypeEvalContext.userInitiated(element.getContainingFile()).withTracing();
   }