Is a Will sufficient documentation to set up a Trust account without having an actual Trust document?

This is a State specific legal question and you might want to ask your legal counsel. Generalizations when dealing with last will and testaments without the review of the specific document is not an easy task.

So, I'll give you the Hornbook response rather than a state specific response. A "testamentary trust" can be established in a will. It has no effect until 1) the testator dies and 2) the estate's personal representative funds the trust. It must have an EIN of its own.

If your bank requires copies of trust documents then you will require a copy of the will certified by the clerk of the court where the will was filed as a matter of public record. (Banks require copies of trusts because they intend to read them, not just to plump up the file.) Any information you would expect to find in an inter vivos trust, you should expect to find in a testamentary trust.

One more question:
A customer has a check made payable to the Estate of Jane Doe. They have a copy of a revocable Trust with an EIN# for Jane Doe. I know that when Jane died, the Revocable Trust became Irrevocable and we do have the EIN#. Can we deposit that Estate check into the Irrevocable trust account or do we have to have Letters of Testamentary where the estate has been probated and an executor set up OR can the Trust off the Irrevocable Trust endorse the check?

The money belongs to the estate and there is no relationship between that money and the irrevocable trust, unless the executor of the estate and the courts determine that is where the money belongs according to the will of the deceased.

What he said; the check is payable to the estate. The estate and the trust are two separate legal entities.

If the money is to end up in the trust under the terms of the will it's the personal representative's job to write a check to the trust.

Thank you all so much