How about this example. I did a sin of talking negatively about 2 priests, one of whom I made my confession to, I confessed that I had bad mouthed a priest a few times.. Do I need give the details or just saying that is enough.
Nope, that's plenty. Kind of sin and number are all that are required. Unless there are particular circuмstances which change the nature of the sin, they are superfluous.
So, with this example, if your "bad-mouthing" involved calumny or detraction, then that would be detraction and calumny. But if it's something short of that, such as "boy he gives lousy sermons" or "that priest has a bad temper" or "I really don't like him." ... which is typically what is meant by bad-mouthing rather than "this priest is having an affair with a female parishioner".