Overlap for Date/Time

I have a spreadsheet that has dates, employee IDs, and start and stop times (designated in military time). I am looking for a formula where two or more times "overlap" on only particular day.

See attached spreadsheet. Sheet labeled "Input" has my source data, and sheet output is what I am trying to accomplish. If it could be done with conditional formatting, that would be fine as well. Otherwise, a formula will work. The main goal is that if two times "overlap", then it be identified as such.

Any ideas on where to begin? Thanks.

Thanks benishiryo. That will work..