throw open the doors

赤字の箇所を説明して下さい。UG→くわた
London (CNN) -- WikiLeaks threw open the doors Friday to its archive of more than a quarter million secret U.S. diplomatic cables, unfiltered and unedited, exposing and possibly endangering confidential diplomatic sources.
http://edition.cnn.com/2011/WORLD/europe/09/02/us.wikileaks/index.html?hpt=hp_t2