This deal cannot happen till the middle of January at the earliest.
The Sixers acquire Brogdon, Grant and Kris Murray. This one is a no-brainer. They trade Tobias Harris' expiring contract, Springer, Martin, House a pick and a pick swap. Harris has been playing well for them this season but I believe that just motivates them more to trade him while he might actually pique some interest around the league.
After seeing what Philly's roster can do to their biggest competition in the Celtics, it seems like RoCo and Batum are becoming very useful assets for them. And though Harris' steady scoring has been key to their streak, it doesn't seem as necessary as finding a more versatile defender at the 4 spot and a steadier PG that compliments Maxey. So ultimately the goal here is to add talent and just fill the holes. There's no desperate need for a star, or scoring.
Portland gets Joe Harris, Bojan Bogdanovic, House, Springer, Martin a future 1st (LAC) and a future pick swap (LAC). Harris and House are probably just seen as expiring contracts to get off their books next season. But as for Springer and Martin, these are cheap young assets to add to their already promising young roster. Which brings us to Bogdanovic, He's still a player that could fetch them yet another package whether it be at the deadline or in the off-season. They get off of Grant's contract, and deal away Murray who has struggled early in his career.
As for Detroit, I thought they could use some efficient scoring in their frontcourt. Bogdanovic has yet to play this season and Joe Harris hasn't looked good at all for them. To land Tobias Harris could be what helps them be competitive now as they approach the play-in/playoffs. Tobias being on an expiring also allows them to re-sign him next season for less or move on from him if they find a better alternative. They get an upgrade at PF without trading away much.