IBKR provides daily statements that report all activity for an account each day.  Trades which occur after the official close of a day for a certain product would not be included in the previous day's statement.  To clarify, here is an example:

You are trading ES futures on 2/15/09.  The ES futures contract begins a new "day" at 15:30 CST.  All of your trades in ES futures prior to 15:30 CST will be shown on your 2/15/09 daily statement.  Those trades which occurred after 15:30 CST on 2/15/09, will not appear on the 2/15/09 daily statement, but rather on the 2/16/09 daily statement.  This is because after 15:30 CST, you are trading ES on the 2/16/09 trade date.