Unsupported parent for detail: <Listbox customerList>

<listbox id="customerList" model="@{myList}" mold="paging" pageSize="2"
				multiple="true" width="800px"
				rows="${custCount}">
				<listhead sizable="true">
					<listheader label="Id" sort="auto(id)"/>
					<listheader label="Name" sort="auto(name)"/>
					<listheader label="Active Date" sort="auto(date)"/>
					<listheader label="Deleted?" />
				</listhead>
				<detail open="false" fulfill="onOpen=/widgets/grid/hierarchy/season.zul" />
	            <listitem self="@{each=myList}" onClick="showEdit(self.getLabel())">
					<listcell label="@{myList.id}" />
					<listcell label="@{myList.name}" />
					<listcell label="@{myList.date}" />
					<listcell label="@{myList.deleted}"/>
				</listitem>
	         </listbox>