Two brothers, one an ex-con and the other a divorced father of two kids, face the foreclosure of their family’s West Texas farm. They team for a skillfully-calculated bank robbing spree that puts them on a collision course with two Texas Rangers determined to take them down.

This is my kind story. Congrats on making the Black List. Figured I'd humbly take a stab at simplifying your log line:

Two brothers, desperate to save the family farm, embark on a bank robbing spree that puts them on a collision course with a pair of determined Texas Rangers.

For starters this needs to be shortened. Is one of the siblings the main character or is this multi protagonist? Usually even in a multi-pro film one character still has the slight lead. I would mainly describe them and then state 'and their 'so & so' brother....'

The goal is there and the stakes but it certainly needs shortening. I also have a few issues much like SydneyPaul above but I don't need to say them again. Take a look at it again and think of the necessities. Hero, Villain, Problem, Goal, Stakes.

Hope this helps.

A few thoughts on your idea:
a) an 'ex-con' seems pretty stereotypical and unsurprising that they would rob a bank. It may work better with a less obvious teaming "a divorced father of two and his Buddhist sister....."?
b) Why a bank-robbing spree? To stop the foreclosure only one robbery would be necessary. A spree my make sense if the motivation is revenge against the bank's greed?
c) It could also be shortened.

So an idea that may provide some use...
"When a divorced father of two and his Buddhist sister face foreclosure on their family's West Texas farm, they plan a breathtaking robbery that puts them on a collision course with two Texas Rangers."