That suggests the line is an autoshape and whoever designed the document has not allowed for how Word can lay out the same document differently on different computers. Depending on what protection is applied to the document, you may be able to select the line and move it. If you do so, though, the line may no longer appear in the 'right' place on the computers where it was designed.

Basically, it's the result of poor document design by someone who doesn't know how to use Word properly.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]