If you are a green card holder, and have extenuating circumstances that require your stay abroad for longer than 12 months, is there a document you can file ahead of time to avoid potential problems with your entry back? Thank you.

File for Re-Entry Permit, form I-131 (http://www.uscis.gov/portal/site/uscis/menuitem.5af9bb95919f35e66f614176543f6d1a/?vgnextoid=b11747a55773d010VgnVCM10000048f3d6a1RCR D&vgnextchannel=db029c7755cb9010VgnVCM10000045f3d6a1 RCRD)
It will be good for two years.