All the payments are registered in Affiliates -> Payments.
Each time a commission is paid, a new payment is registered in the table.
If the commission has been set to “paid” manually, the payment will be generated with the status “Completed”. By automatic payments via PayPal, the payment will acquire the “Pending” status until PayPal notifies that the payment has been made.
In order to view payment details you can click on its ID.