<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019dac98-f873-7c9e-9cdf-5ce7e182904b,g:daef29fd-bd82-4269-9b7a-a76ffb2eaa97-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel"/>
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_ck0001140019_C000068094Member_label_en-US" xlink:label="lab_ck0001140019_C000068094Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000068094 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000068094Member_documentation_en-US" xlink:label="lab_ck0001140019_C000068094Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000068094</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000068094Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000068094Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000068094Member" xlink:to="lab_ck0001140019_C000068094Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001140019_C000078453Member_label_en-US" xlink:label="lab_ck0001140019_C000078453Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000078453 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000078453Member_documentation_en-US" xlink:label="lab_ck0001140019_C000078453Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000078453</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000078453Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000078453Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000078453Member" xlink:to="lab_ck0001140019_C000078453Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001140019_C000042674Member_label_en-US" xlink:label="lab_ck0001140019_C000042674Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000042674 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000042674Member_documentation_en-US" xlink:label="lab_ck0001140019_C000042674Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000042674</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000042674Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000042674Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000042674Member" xlink:to="lab_ck0001140019_C000042674Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001140019_C000078454Member_label_en-US" xlink:label="lab_ck0001140019_C000078454Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000078454 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000078454Member_documentation_en-US" xlink:label="lab_ck0001140019_C000078454Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000078454</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000078454Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000078454Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000078454Member" xlink:to="lab_ck0001140019_C000078454Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001140019_C000042670Member_label_en-US" xlink:label="lab_ck0001140019_C000042670Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000042670 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000042670Member_documentation_en-US" xlink:label="lab_ck0001140019_C000042670Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000042670</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000042670Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000042670Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000042670Member" xlink:to="lab_ck0001140019_C000042670Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001140019_C000042673Member_label_en-US" xlink:label="lab_ck0001140019_C000042673Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000042673 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000042673Member_documentation_en-US" xlink:label="lab_ck0001140019_C000042673Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000042673</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000042673Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000042673Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000042673Member" xlink:to="lab_ck0001140019_C000042673Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001140019_C000042669Member_label_en-US" xlink:label="lab_ck0001140019_C000042669Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">C000042669 [Member]</link:label>
    <link:label id="lab_ck0001140019_C000042669Member_documentation_en-US" xlink:label="lab_ck0001140019_C000042669Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">C000042669</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001140019_C000042669Member" xlink:href="ck0001140019-20260423.xsd#ck0001140019_C000042669Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001140019_C000042669Member" xlink:to="lab_ck0001140019_C000042669Member" xlink:type="arc" order="1"/>
  </link:labelLink>
</link:linkbase>