New company asking for other offer letter

Hi guys, I recently got an offer from company B. I told them I have an offer from company A and would expect a hike on that.

I even shared a redacted version of the offer I was holding with the company name, HR details etc striked out.

But they're insisting on sharing the full document, which I feel is not really necessary.

Is this a norm or is sharing the salary annexure of the in hand offer enough ?

Appreciate any suggestions.