For some reason, the <th> element in any tested version of IE (9+) wasn't implicitly inheriting the text-align property from the table container (in all versions of IE, even though the developer tools indicated it was at least trying to inherit it), so I needed to add an explicit statement to force the inheritance. I initially thought it was because I had omitted the <tr> element, but alas, this didn't fix the problem. I will update the comment to reflect the scope of this fix, and I will also change the value to be "inherit" instead of "left" as to make the intent more explicit.