I see two questions here.
Most of the answers attacks (very well, some +1's around here!) the secondary question, but I'll try to focus on the first, in subject, question:
What to do when team members are overburdened by process?
Let's assume we're chit chatting about this question in the IT lounge of a big, Forbes 500, Financial company.
It's common sense that IT folks simply HATE bureaucracy. IT people tend to anarchism, in a good sense. So, throwing a pile of paperwork on them will for sure create the chit chatting on the previous paragraph.
So, back to the original question... what to do about it?
In this sense, SBWorks in his answer raises a very important point: documentation is not senior management only. Especially in big companies like this we are, in the 18 floor, this gray carpet and windows from top to bottom of the wall, documentation is vital. Is mandatory. Is regulatory. Bottomline:
It's not a matter of doing 'enough' documentation. Is a matter of doing all mandatory documentation.
And doing so as better as possible. You for sure don't want those big guys from Wallstreet hating you.
And here I believe the best answer is Mark's, with:
Enough is what helps the team.
Sounds simple, right? It's not. Definitely. IT keeps complaining. IT complains of everything.
So, to have IT stopping complaining about the documentation, explain them the underlying reasons for the usability of so much documentation. Before try to explain to them, make sure you accept the answer for yourself. If you find no reason, go talk to the people responsible for the process and discuss with them.
The idea, in de end, is to get rid of the documentation no one explained hot to use and keep very attached to the documentation in place. Doing so, there will never be 'documentation overload'.