what type of fraud is regina committing?

Case 1

Regina has finally landed her dream job at Abercroanie & Fetch. After just a couple of days on the job, we find out why. Often, when people return merchandise, Regina will ring up on the register that they returned something of more value than it was really worth. She then pockets the extra cash and gives the customer the amount due. Regina finds this method very effective because people really are returning something, so inventories and the reg- ister totals won’t be out of balance at the end of the day.

1.       What type of fraud is Regina committing?

2.       How could her employer detect this kind of fraud?