This article written by Gary Brooks, will help understanding which financial documents to keep, and for how long you should keep them. "Are you tired of the ever-increasing volume of financial documents, but not sure what you can toss? What follows is a general guide of what records to keep and for how long..."
http://www.usatoday.com/story/money/personalfinance/2015/06/28/adviceiq-financial-documents-keep/29378955/