Whether or not XBRL GL should move from the use of tuples to XBRL Dimensions has been asked so much that Eric Cohen and Gianluca Garbellotto, two long time contributors to and proponents of XBRL GL, wrote a document XBRL Dimensions and XBRL GL: Why or Why Not (An Apologetic) 1.0 which discusses this issue.
Here is the abstract of that document:
XBRL GL makes extensive use of tuples, and a "dimensional" version of XBRL GL is not in the making. This document explains why, given the type of information that XBRL GL is designed to represent, replacing tuples with dimensions in XBRL GL's architecture would not be a good idea.
Any student of XBRL should understand XBRL GL, its relation to other forms of XBRL, the connection point between the two, and other such issues.
My personal view is that there is no real need for an XBRL Dimensions based representation of XBRL GL. Although, I also would not use XBRL GL for things which many people would, preferring the consistency of always using XBRL Dimensions.
The modeling approach XBRL GL uses is quite useful in many cases and gets in the way in others. The important thing is to understand the pros and cons of each modeling approach BEFORE you commit to one way or another. Each has it's place.