It's the largest single fine for an on-field incident in league history, though there have been a few harsher penalties. Bill Belichick was docked $500,000 for his role in the Spygate scandal, and Ray Lewis was fined $250,000 for, um, obstructing justice in a murder case. We're also not counting game checks lost due to suspension.
The previous largest single fine was James Harrison's $75,000, for going helmet-to-helmet one too many times.
Suh, like Harrison, is a repeat offender—he had previously been fined a total of $77,500 for five separate incidents, and lost out on another $165,000 for a two-game suspension.