Advice is to override the core Magento cms_page_view.xml in the following location.
app/design/frontend/[Vendor_Theme]/Magento_Cms/layout/override/base/cms_page_view.xml
<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
<body>
<referenceContainer name="content">
<block class="OuterEdge\Page\Block\Page" name="cms_page" template="content.phtml"/>
</referenceContainer>
</body>
</page>
http://devdocs.magento.com/guides/v2.0/frontend-dev-guide/layouts/layout-override.html