Change the Document date to not default in on Payables/Purchasing Invoice Windows

The users keep forgetting to change the document date on the Payables Transaction Entry, Purchasing Invoice Entry and the Receivings Transaction Entry windows. They would like to change this field to be blank on every new transaction so that the user is always forced to check the document date and enter the correct one. I am unable to change the AutoCopy=False in Modifier. Would that be the correct property to change? Is there a way to accomplish disabling the field from auto populating?

Thanks!