The Catholic Church does not use the term “Ecumenical Churches”. Rather, they speak of “ecumenism”, which is the Church’s effort for unity among all Christians. As Br. Rich pointed out, the Church recognizes all validly baptized people as Christians. These validly baptized non-Catholics are those to whom the Church desires unity, which is what the ecumenical movement is all about. You might look at the Vatican II Decree on Ecumenism for more information.