Most credit cards calculate interest at the end of the cycle and add it to the balance: this reduces the available credit. As an extreme case, when this goes over limit the cardholder is required to make a larger than normal payment to bring it back down.
I know of a credit union credit card that does it a little differently by not counting interest against the card limit. Naturally interest is still deducted from payments and the principal portion is applied to the balance which become available credit again. For the extreme scenario, the minimum payment does not increase as it did above, at least not when the "overlimit" is due to new interest.
I once looked at the agreements to find where this accounting is defined but had no luck. So my questions:
Do these concepts have names?
Is this common among credit unions?
Is this generally limited to credit unions, being that they're more consumer-friendly?
Is interest receivable handled differently in the books of two creditors or is this just a matter of calculating available credit and minimum payments in slightly different ways with no difference behind the scenes from an accountant's perspective?
Are there any regulations on this topic worth noting?
Edit: I am asking strictly out of curiosity. Please do not presume this indicates a lack of credit responsibility on my part. The overlimit detail is not really even fundamental to the question except that I think it might be insightful about the credit union's perspective.