Reactor Corp. has incurred utility costs for the month of December, but the utility company does not send out its bills until the 15th of the following month. Reactor does not plan on recording the utility costs until it receives the bill on January 15. Assuming Reactor prepares adjusting entries monthly, when should it record these costs-in December or in January? Identify the date of the entry you believe should be used and which accounts should be debited and credited.