Table header background color not filling entire cell

I have a table header with a background color.  Problem is, I have some header cells that have one line of text and others with two lines.  The two line cells have a background color that pretty much fills the cell, but the one line cells have the background color only around the text with white space above and below.  

Here are my current CCS properties for the header...

table.sortable a.sortheader {
    background-color: #e0b4a6;
    color: black;
    font-weight: bold;
    text-decoration: underline;
    display: block;
      PADDING-RIGHT: 4px;
      PADDING-LEFT: 4px
}