Duplicate a dimension attribute in a fact table

I have a dim_transaction table containing all the different kind of transactions I can execute on a bank account. This table contains for every transaction an attribute telling whether the transaction is a debit or a credit. In my transactions fact table I want to be able to distinguish between credit an debit transactions. Is it a good idea for your point of view to add a dimension debit_credit in the fact table copied from the dimension table ? Or should I access it via my dimension table in my cube definition?

The measures should be negative or positive depending on its effect on the balance. That should be sufficient to determine which are credits or debits.

I need to be able to analyse credits vs debits so I need an axis of analysis to do that.
Anyway, in a general case does that make sense to duplicate a dimension attribute in a fact table as a degenerated dimension?

Why would you need to be able to distinguish this from the fact table without using the dimension table?

Do not create a degenerate dimension as you cannot then use this attribute properly in a BI tool.