The most important church document on ecumenism might be this video on YouTube. Apparently, Pope Francis has a good friend name Tony Palmer, an Anglican active in the Pentecostal movement. The Pope asked his friend to take a video of himself on his iPhone in order to share it with a large Protestant conference that he was attending.
In the video, Pope Francis says he wants to speak from the heart. He goes on to say that he has a great desire for the separation between Catholics and Protestants to end and to give way to communion. He uses the story of Joseph and his brothers to convey a simple message: I am your brother.
The message is even more amazing if you see the way that Tony Palmer explains the video, pleads for the divisions among Christians to end, and then records Kenneth Copeland giving a video response back to Pope Francis.