Problem: Many companies keep a small amount of cash on hand to reimburse employees for small expenses that arise in the course of business. This account is called Petty Cash and is accounted for at the end of a period, with expenses grouped together by accounts such as Office Supplies, Meals, Travel, and Other Expenses, rather than record each individual expense that is reimbursed.
The reasoning behind recording the transactions in this manner relates to which of the following accounting principles?