As the screenshot shows the Logos version of NIV2011 (anglicised) has an em dash (or it could be an en dash) in Hebrews 7:26 (also happens elsewhere) whereas the Bible Gateway version shows a hyphen (I don't have a paper copy to check which is "original")

For our purposes - printing out portions of scripture for readings in church - the hyphen would be preferable.
Why is there the discrepancy, which is "correct"?
Thanks, Graham