[xsl] Simple variable problem

The below code attempts to go through a list of people and then grab
their associated expenses from a dynamic ASP page serving up XML.

At the line which contains the asp file I use $id incorrectly as a
marker. What is the correct syntax to get the value of the present
value of 'id'

<xsl:for-each select="Records/Record">
	<div id="record">
		<div id="line1">
			<span id="date">
				<xsl:value-of select="date" />
			</span>
			<span id="expenses">
				<xsl:value-of
select="document('http://www.server.org/getExpenses.asp?key=activity_id&amp;val=$id&amp;table=Expenses')"
/>
			</span>
		</div>
	</div>
</xsl:for-each>

Steve Yeago
http://www.yeago.net