diff --git a/src/document/Document.ts b/src/document/Document.ts
new file mode 100644
index 0000000..0db893a
--- /dev/null
+++ b/src/document/Document.ts
@@ -0,0 +1,37 @@
+/**
+ * Document (quote) interface
+ *
+ *  Copyright (C) 2010-2019 R-T Specialty, LLC.
+ *
+ *  This file is part of the Liza Data Collection Framework.
+ *
+ *  liza is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * The term "Quote" is synonymous with "Document"; this project is moving
+ * more toward the latter as it is further generalized.
+ */
+
+/**
+ * Document identifier
+ */
+export type DocumentId = NominalType<number, 'DocumentId'>;
+
+
+/**
+ * Quote (Document) id
+ *
+ * Where the term "Quote" is still used, this will allow for type
+ * compatibility and an easy transition.
+ */
+export type QuoteId = DocumentId;
diff --git a/src/server/token/TokenDao.ts b/src/server/token/TokenDao.ts
index c5a7d99..75b7710 100644
--- a/src/server/token/TokenDao.ts
+++ b/src/server/token/TokenDao.ts
@@ -29,6 +29,7 @@ import {
 } from "./TokenQueryResult";
 
 import { TokenId, TokenNamespace } from "./Token";
+import { DocumentId } from "../../document/Document";
 
 
 /**
@@ -91,14 +92,14 @@ export default class TokenDao
      * The token entry is entered in the token log, and then the current
      * entry is updated to reflect the changes.  The operation is atomic.
      *
-     * @param quote_id unique quote identifier
+     * @param doc_id   unique document identifier
      * @param ns       token namespace
      * @param token    token value
      * @param data     token data, if any
      * @param status   arbitrary token type
      */
     updateToken(
-        quote_id: number,
+        doc_id:   DocumentId,
         ns:       TokenNamespace,
         token_id: TokenId,
         type:     TokenType,
@@ -126,7 +127,7 @@ export default class TokenDao
         return new Promise( ( resolve, reject ) =>
         {
             this._collection.update(
-                { id: +quote_id },
+                { id: +doc_id },
                 {
                     $set: token_data,
                     $push: token_log
@@ -149,19 +150,19 @@ export default class TokenDao
 
 
     /**
-     * Retrieve existing token under the namespace NS, if any, for the quote
-     * identified by QUOTE_ID
+     * Retrieve existing token under the namespace NS, if any, for the doc
+     * identified by DOC_ID
      *
      * If a TOKEN_ID is provided, only that token will be queried; otherwise,
      * the most recently created token will be the subject of the query.
      *
-     * @param quote_id quote identifier
+     * @param doc_id   document identifier
      * @param ns       token namespace
      * @param token_id token identifier (unique to NS)
      *
      * @return token data
      */
-    getToken( quote_id: number, ns: TokenNamespace, token_id: TokenId ):
+    getToken( doc_id: DocumentId, ns: TokenNamespace, token_id: TokenId ):
         Promise<TokenData|null>
     {
         const root        = this._genRoot( ns ) + '.';
@@ -179,7 +180,7 @@ export default class TokenDao
         return new Promise( ( resolve, reject ) =>
         {
             this._collection.findOne(
-                { id: +quote_id },
+                { id: +doc_id },
                 { fields: fields },
                 ( err: Error|null, data: TokenQueryResult ) =>
                 {
diff --git a/test/server/token/TokenDaoTest.ts b/test/server/token/TokenDaoTest.ts
index ad06159..c992632 100644
--- a/test/server/token/TokenDaoTest.ts
+++ b/test/server/token/TokenDaoTest.ts
@@ -34,6 +34,8 @@ import {
     TokenNamespace,
 } from "../../../src/server/token/Token";
 
+import { DocumentId } from "../../../src/document/Document";
+
 
 import { expect, use as chai_use } from 'chai';
 chai_use( require( 'chai-as-promised' ) );
@@ -46,7 +48,7 @@ describe( 'server.token.TokenDao', () =>
         it( 'updates token with given data', () =>
         {
             const field     = 'foo_field';
-            const qid       = 12345;
+            const did       = <DocumentId>12345;
             const ns        = <TokenNamespace>'namespace';
             const tok_id    = <TokenId>'tok123';
             const tok_type  = 'DONE';
@@ -64,7 +66,7 @@ describe( 'server.token.TokenDao', () =>
                         data:      data,
                     };
 
-                    expect( selector.id ).to.equal( qid );
+                    expect( selector.id ).to.equal( did );
 
                     expect( given_data ).to.deep.equal( {
                         $set:  {
@@ -87,7 +89,7 @@ describe( 'server.token.TokenDao', () =>
             };
 
             return new Sut( coll, field, () => timestamp )
-                .updateToken( qid, ns, tok_id, tok_type, data );
+                .updateToken( did, ns, tok_id, tok_type, data );
         } );
 
 
@@ -106,7 +108,11 @@ describe( 'server.token.TokenDao', () =>
 
             return expect(
                 new Sut( coll, 'foo', () => <UnixTimestamp>0 ).updateToken(
-                    0, <TokenNamespace>'ns', <TokenId>'id', 'DONE', null
+                    <DocumentId>0,
+                    <TokenNamespace>'ns',
+                    <TokenId>'id',
+                    'DONE',
+                    null
                 )
             ).to.eventually.be.rejectedWith( expected_error );
         } );
@@ -116,7 +122,7 @@ describe( 'server.token.TokenDao', () =>
     describe( '#getToken', () =>
     {
         const field  = 'get_field';
-        const qid    = 12345;
+        const did    = <DocumentId>12345;
         const ns     = <TokenNamespace>'get_ns';
 
         const expected_status: TokenStatus = {
@@ -212,7 +218,7 @@ describe( 'server.token.TokenDao', () =>
 
                 return expect(
                     new Sut( coll, field, () => <UnixTimestamp>0 )
-                        .getToken( qid, ns, tok_id )
+                        .getToken( did, ns, tok_id )
                 ).to.eventually.deep.equal( expected );
             } )
         );
@@ -233,7 +239,7 @@ describe( 'server.token.TokenDao', () =>
 
             return expect(
                 new Sut( coll, 'foo', () => <UnixTimestamp>0 )
-                    .getToken( 0, <TokenNamespace>'ns', <TokenId>'id' )
+                    .getToken( <DocumentId>0, <TokenNamespace>'ns', <TokenId>'id' )
             ).to.eventually.be.rejectedWith( expected_error );
         } );
     } );