The feel-good biographical documentary Won’t You Be My Neighbor? is delivering big box office returns along with a heaping helping of uplifting nostalgia and positive messaging. The Fred Rogers retrospective from Oscar-winning documentary filmmaker Morgan Neville and Focus Features is on pace to cross $20 million at the domestic box office this weekend, a tally that only a handful of previous documentaries have reached. Won’t You Be My Neighbor? is easily the top-grossing biographical documentary of all time, earning that distinction once it passed the $8.4 million mark for the 2015 Amy Winehouse pic, Amy. It’s also got the biggest documentary box office in five years and is currently placed 14th all-time in this list, without adjusting for inflation.

As THR reports, that success was a surprise even to the filmmaker himself. Last year’s top-earning documentary was Disney’s nature picture Born in China with $13.9 million; the closest biographical doc, Raoul Peck‘s James Baldwin picture I Am Not Your Nego, came in at about half that. That film earned an Oscar nod for Best Documentary Feature, though the award ultimately went to ESPN’s O.J. Made in America. So not only is Won’t You Be My Neighbor? reclaiming some of that big-screen audience for bio-docs, it’s also showing that the box office potential for such films still exists.

Neville commented on just that phenomenon:

“Anybody who says they aren’t surprised how how well our film has done is lying … A year ago, it seems like you couldn’t pay people to go see documentaries in theaters. There were a bunch of big acquisitions at Sundance in 2017, but nothing did so well. People thought the market for documentaries was extinct … We thought that if our film did anything close to $10 million, it would be a home run.”

Neville’s Oscar-winning work Twenty Feet from Stardom topped out at just under $5 million at the box office back in 2013; Won’t You Be My Neighbor? has already eclipsed that four times over and shows no signs of stopping anytime soon. Box-office prognosticators see Won’t You Be My Neighbor? grossing between $22 million and $25 million by the end of its run, putting it on par with Michael Moore‘s 2012 Oscar-winner pic Bowling for Columbine ($21.6 million, when adjusted for inflation).

Universal, parent company of Focus, recently announced that Won’t You Be My Neighbor? will be released digitally on August 21, followed by a DVD/Blu-ray release on September 4th, continuing to expand the picture’s reach and revenue, and propagating its positive message.

“Won’t You Be My Neighbor? has become a phenomenon. It’s cathartic,” said Focus president of distribution Lisa Bunnell. Neville added, “Documentaries in general are telling the types of complex adult stories that aren’t getting told in Hollywood very often anymore. They are contagious.”