Concatenate three columns then split into rows

I need to concatenate these three columns, separated by delimiter. Sometimes there will only be one ID, sometimes two, and sometimes three. If there is no ID, it's a null value.

Here is what I'm doing to attempt this:

= Table.AddColumn(#"Renamed Columns", "Text.Combine", each Text.Combine({[Employee ID],[Employee ID2],[Employee ID3]},"; "))

but as you can see, I'm getting errors in the newly created column. Here's the error:

Once the combined column is created, I'll need to create duplicate row for each line with a ID2 and ID3.

Please help. This seemed like it should be straight-foward but, apparently not.

Thanks!!!