Highlighting is not working with docValues only String field

Highlighting is not working with docValues only String field.  Need to check SortableTextField as mentioned by erickerickson

Schema:
<schema name="core" version="1.6">
  <uniqueKey>id</uniqueKey>
  <fieldType name="string" class="solr.StrField" sortMissingLast="true"/>
  <field name="id" type="string" docValues="true" indexed="true" required="true"/>
  <field name="name" type="string" docValues="false" indexed="true" stored="true"/>
  <field name="name1" type="string" docValues="true" indexed="true" stored="false"/>
  <copyField source="name" dest="name1"/>
</schema>

Data:
[

{"id":1,"name":"Testing line 1"}

,

{"id":2,"name":"Testing line 2"}

,

{"id":3,"name":"Testing line 3"}

]

Query:
http://localhost:8983/solr/test/select?q=Testing*&df=name&hl=true&hl.fl=name,name1

Response:
{"response":{"numFound":3,"start":0,"docs":[

{"id":"1","name":"Testing line 1","name1":"Testing line 1"}

,{"id":"2","name":"Testing line 2","name1":"Testing line 2"},{"id":"3","name":"Testing line 3","name1":"Testing line 3"}]},"highlighting":{"1":

{"name":["<em>Testing line 1</em>"]}

,"2":

{"name":["<em>Testing line 2</em>"]}

,"3":

{"name":["<em>Testing line 3</em>"]}

}}