Agile Requirements - what's beyond the user story?

In the my Previous blog I talked about a metaphor to illustrate requirements evolving from a 1-liner, to a paragraph, to a 1-pager, and then to multiple pages. In the process of building systems using agile approaches many teams have forgotten, or worse have never known how to document details around requirements. There's that pesky agile value - "working software over comprehensive documentation." Too many teams take this to mean we no longer have to write anything down. Not so fast cowboys.