Getting Logoff time on behalf of Logon Time RetailTransactionTable

Hello !
I am developing a report in which user will provide Stores and date ranges. I need to show the Logon Logoff time of selected stores that I can retrieve from RetailTransactionTable. Output should be like

Store          Date          Logon Time         Logoff Time
123          9/23/2015     01:00PM              06:00PM

123          9/23/2015     07:00PM                 -
123          9/24/2015          -                     12:45AM


I need to know how can i do it or how can i find which logoff transaction is corresponding to which login transaction and vice versa. 
Thanks in advance.