By "travel documents," do you mean your Magical Express vouchers/luggage tags? If so, they do typically arrive about a month out, and you may want to call Disney to inquire.
(FWIW, if you are traveling "carryon only" or otherwise don't need the luggage tags, you may not need the Magical Express packet at all, since the Magical Express entitlement will also be coded onto your Magic Bands. At least, that's what my family discovered when we arrived in Orlando last week. All we needed were the Magic Bands. The paper voucher stayed in our luggage.)