diff --git a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XSourcePositionImpl.java b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XSourcePositionImpl.java
index 148b3861f9f5..001fd9e9c626 100644
--- a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XSourcePositionImpl.java
+++ b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XSourcePositionImpl.java
@@ -26,6 +26,7 @@ import com.intellij.openapi.vfs.impl.http.HttpVirtualFile;
 import com.intellij.pom.Navigatable;
 import com.intellij.psi.PsiElement;
 import com.intellij.testFramework.LightVirtualFile;
+import com.intellij.util.DocumentUtil;
 import com.intellij.xdebugger.XDebuggerUtil;
 import com.intellij.xdebugger.XSourcePosition;
 import org.jetbrains.annotations.NotNull;
@@ -75,7 +76,7 @@ public class XSourcePositionImpl implements XSourcePosition {
       if (document == null) {
         return null;
       }
-      int line = offset <= document.getTextLength() ? document.getLineNumber(offset) : -1;
+      int line = DocumentUtil.isValidOffset(offset, document) ? document.getLineNumber(offset) : -1;
       return new XSourcePositionImpl(file, line, offset);
     }
     finally {