Honestly you need to talk to someone about that because you don't want to end up with a crappy grade because your teachers an idiot.

I am saddened by the American school system.

What sort of details did you write? If you summarized the original work too much and did not write enough actual analysis of the work, that might be why the teacher marked you down. For example if 3/4 of the paragraph is a summary of a section, then that isn't sufficient analysis. Your teacher can't give you points if you don't follow the assignment.

Hm, maybe OP wrote like a 20 page paper when his/her teacher only asked for around 5? I find it hard to believe that a teacher would mark a good paper down for too much unless it was an excess amount

Your teacher may very well have a point. It is very important to be able to prioritise what to add, and what to leave out. Once you go to university or into the real world (work), you will often meet restrictions on both time and more importantly length of your works. People won't be interested in reading all sorts of details when they really just need what is relevant for the task in question.

You need to charge in there to a higher authority and complain because that is just outrages

FYL, but your teacher is right. Take it from a designer, in the real world when articles and essays are getting published we will tell the authors "you have room for 1300 words, that's it" and if they go over we will just take off the bottom paragraphs. We don't have time to read through and cut down your work, so it's very important you learn to do so yourself if your job requires any report writing at all.

Same here. totally feel u. accordingly I had too much details too

This isn't your normal asshole teacher, this is an advanced asshole teacher

Honestly some teachers suck!!

So you're saying your analysis was too analytical for your analytical paper?

Too much detail in an analytical work may have seemed like padding to disguise the fact there was very little actual analysis and conclusion going on. If you bury the reader in background details but don't actually spend most of the time analyzing those details, or only analyze one or two of the introduced details there is no reason for them to be included other than to take up space.