diff --git a/lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextSimpleDocValuesFormat.java b/lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextSimpleDocValuesFormat.java
index 053861a25d5..19aa562a5fd 100644
--- a/lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextSimpleDocValuesFormat.java
+++ b/lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextSimpleDocValuesFormat.java
@@ -156,8 +156,14 @@ public class SimpleTextSimpleDocValuesFormat extends SimpleDocValuesFormat {
       SimpleTextUtil.write(data, Long.toString(minValue), scratch);
       SimpleTextUtil.writeNewline(data);
 
-      // build up our fixed-width "simple text packed ints" format
-      int maxBytesPerValue = BigInteger.valueOf(maxValue).subtract(BigInteger.valueOf(minValue)).toString().length();
+      assert maxValue >= minValue;
+
+      // build up our fixed-width "simple text packed ints"
+      // format
+      BigInteger maxBig = BigInteger.valueOf(maxValue);
+      BigInteger minBig = BigInteger.valueOf(minValue);
+      BigInteger diffBig = maxBig.subtract(minBig);
+      int maxBytesPerValue = diffBig.toString().length();
       StringBuilder sb = new StringBuilder();
       for (int i = 0; i < maxBytesPerValue; i++) {
         sb.append('0');
@@ -167,8 +173,10 @@ public class SimpleTextSimpleDocValuesFormat extends SimpleDocValuesFormat {
       SimpleTextUtil.write(data, PATTERN);
       SimpleTextUtil.write(data, sb.toString(), scratch);
       SimpleTextUtil.writeNewline(data);
+
+      final String patternString = sb.toString();
       
-      final DecimalFormat encoder = new DecimalFormat(sb.toString(), new DecimalFormatSymbols(Locale.ROOT));
+      final DecimalFormat encoder = new DecimalFormat(patternString, new DecimalFormatSymbols(Locale.ROOT));
       return new NumericDocValuesConsumer() {
         int numDocsWritten = 0;
 
@@ -176,7 +184,9 @@ public class SimpleTextSimpleDocValuesFormat extends SimpleDocValuesFormat {
         public void add(long value) throws IOException {
           assert value >= minValue;
           Number delta = BigInteger.valueOf(value).subtract(BigInteger.valueOf(minValue));
-          SimpleTextUtil.write(data, encoder.format(delta), scratch);
+          String s = encoder.format(delta);
+          assert s.length() == patternString.length();
+          SimpleTextUtil.write(data, s, scratch);
           SimpleTextUtil.writeNewline(data);
           numDocsWritten++;
         }
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/SimpleDVConsumer.java b/lucene/core/src/java/org/apache/lucene/codecs/SimpleDVConsumer.java
index 6b359996f6f..02ef1d331be 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/SimpleDVConsumer.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/SimpleDVConsumer.java
@@ -91,7 +91,7 @@ public abstract class SimpleDVConsumer implements Closeable {
         if (liveDocs == null || liveDocs.get(i)) {
           long val = docValues.get(i);
           minValue = Math.min(val, minValue);
-          maxValue = Math.min(val, maxValue);
+          maxValue = Math.max(val, maxValue);
         }
         mergeState.checkAbort.work(300);
       }
diff --git a/lucene/core/src/test/org/apache/lucene/TestDemoDocValue.java b/lucene/core/src/test/org/apache/lucene/TestDemoDocValue.java
index 2347e073b6f..dc1c55c209a 100644
--- a/lucene/core/src/test/org/apache/lucene/TestDemoDocValue.java
+++ b/lucene/core/src/test/org/apache/lucene/TestDemoDocValue.java
@@ -329,12 +329,12 @@ public class TestDemoDocValue extends LuceneTestCase {
     IndexWriter iwriter = new IndexWriter(directory, iwc);
     Document doc = new Document();
     doc.add(newField("id", "0", StringField.TYPE_STORED));
-    doc.add(new PackedLongDocValuesField("dv", 1));
+    doc.add(new PackedLongDocValuesField("dv", -10));
     iwriter.addDocument(doc);
     iwriter.commit();
     doc = new Document();
     doc.add(newField("id", "1", StringField.TYPE_STORED));
-    doc.add(new PackedLongDocValuesField("dv", 3));
+    doc.add(new PackedLongDocValuesField("dv", 99));
     iwriter.addDocument(doc);
     iwriter.forceMerge(1);
     iwriter.close();
@@ -347,9 +347,9 @@ public class TestDemoDocValue extends LuceneTestCase {
       StoredDocument doc2 = ireader.leaves().get(0).reader().document(i);
       long expected;
       if (doc2.get("id").equals("0")) {
-        expected = 1;
+        expected = -10;
       } else {
-        expected = 3;
+        expected = 99;
       }
       assertEquals(expected, dv.get(i));
     }
@@ -386,6 +386,34 @@ public class TestDemoDocValue extends LuceneTestCase {
     directory.close();
   }
   
+  public void testRange2() throws IOException {
+    Analyzer analyzer = new MockAnalyzer(random());
+
+    Directory directory = newDirectory();
+    // we don't use RandomIndexWriter because it might add more docvalues than we expect !!!!1
+    IndexWriterConfig iwc = newIndexWriterConfig(TEST_VERSION_CURRENT, analyzer);
+    iwc.setMergePolicy(newLogMergePolicy());
+    IndexWriter iwriter = new IndexWriter(directory, iwc);
+    Document doc = new Document();
+    doc.add(new PackedLongDocValuesField("dv", -8841491950446638677L));
+    iwriter.addDocument(doc);
+    doc = new Document();
+    doc.add(new PackedLongDocValuesField("dv", 9062230939892376225L));
+    iwriter.addDocument(doc);
+    iwriter.forceMerge(1);
+    iwriter.close();
+    
+    // Now search the index:
+    IndexReader ireader = DirectoryReader.open(directory); // read-only=true
+    assert ireader.leaves().size() == 1;
+    NumericDocValues dv = ireader.leaves().get(0).reader().getNumericDocValues("dv");
+    assertEquals(-8841491950446638677L, dv.get(0));
+    assertEquals(9062230939892376225L, dv.get(1));
+
+    ireader.close();
+    directory.close();
+  }
+  
   public void testDemoBytes() throws IOException {
     Analyzer analyzer = new MockAnalyzer(random());