If you're looking to shave some time off of your test documentation tasks, take a look at working some charters into your test plan so you have fewer scripted test cases to write. Charters are simple to document - you start with defining a mission, an anticipated length, and if you'd like a bit more structure you can include a bullet-list of coverage items so you're sure the person who executes the charter hits all the critical parts. Contrast that with a typical Microsoft Word test case template which includes columns for step, expected result, screenshots, data, setup tasks, comments, etc... It's just a lot of work, for (many times) very little return. If you have not tried using charters before, check em' out.
This tip was part of a brainstorm developed at the September 2011 Indianapolis Workshop on Software Testing on the topic of "Documenting for Testing." The attendees of that workshop (and participants in the brainstorm) included: Charlie Audritsh, Scott Barber, Rick Grey, Michael Kelly, Natalie Mego, Charles Penn, Margie Weaver, and Tina Zaza.