Can anyone tell me if these are allowed by Northwest?

First ticket Madison-Seattle roundtrip
Jan 3 MSN-DTW-SEA
Jan 15 SEA-DTW-MSN

Second ticket Seattle-Tokyo roundtrip
Jan 3 SEA-DTW (red eyes)
Jan 4 DTW-NRT
Jan 15 SEA-DTW (red eyes)
Jan 16 DTW-MSN