Decker worked almost 40 years as a contract cartoonist for the New Yorker
. He started out in 1929 with the magazine and then eventually worked his way up to becoming well-known on the New Yorker'
s pages for cartoons. Decker's humor covers a broad spectrum from changing times to even his large family. Decker's work in ink and watercolor had been featured in several area exhibitions.
He did illustrations for "Look" and the "Saturday Evening Post"
and did a number of advertisements for the "Philadelphia Evening Bulletin".