AA 6486 then UA 2142 at O'Hare
Detroit → Chicago → Nashville
Timetable, Chicago time
17:29AA 6486 from Detroit at the gate
14:05UA 2142 to Nashville leaves the gate
20 h 36 apart on the timetable, overnight
UA 2142 leaves 20 h 36 after AA 6486 arrives on the timetable: more than half a day, so not a connection we count.