In the bad old pre-McNamara days at DTW, all Intl flights (incl NW) arrived at the small Intl terminal, and NW planes were towed to the main terminal for departure. Intl-dom connecting passengers had an airside bus after immigration-customs-baggage recheck to the main terminal. Total PITA even if you were a Detroit passenger, because your car probably was parked in the main-terminal deck, which was not in walking distance from the Intl terminal.