AA 6486 then UA 3534 at O'Hare
Detroit → Chicago → Louisville
Timetable, Chicago time
17:29AA 6486 from Detroit at the gate
14:30UA 3534 to Louisville leaves the gate
21 h 01 apart on the timetable, overnight
UA 3534 leaves 21 h 01 after AA 6486 arrives on the timetable: more than half a day, so not a connection we count.