DL 3747 then DL 3839 at Salt Lake City
Sacramento → Salt Lake City → Helena
Timetable, Salt Lake City time
22:07DL 3747 from Sacramento at the gate
20:55DL 3839 to Helena leaves the gate
22 h 48 apart on the timetable, overnight
DL 3839 leaves 22 h 48 after DL 3747 arrives on the timetable: more than half a day, so not a connection we count.