This one is thanks to the legend Coke & Taco (love to hear those words). There are so many ways you can works this both ways. You can look via DTW or via MSP connect via LAX or NYC etc etc. Just play with this one as the yields are HUGE and the price is LOW! Once you find open dates with ITA Matrix tinker around on Delta.com for best routes.
In case you missed it look at THIS Flyertalk link.