Complex sentence: After Pan Am's demise in 1991 Delta Air Lines took over ownership of the terminal and was its only occupant until its closure in 2013, it had a connector to Terminal 2, Delta's other terminal.
Split into simpler sentences: After Pan Am's demise in 1991 Delta Air Lines took over ownership of the terminal and was its only occupant until its closure in 2013. It had a connector to Terminal 2, Delta's other terminal.