From an NFP article on the 10 players with the highest cap numbers in 2014:

9. Aaron Rodgers (QB)-Green Bay Packers: $17.55 million

Rodgers is the highest-paid player in NFL history (by average yearly salary). He signed a five-year, $110 million contract extension in 2013 containing $54 million in guarantees, which included a $35 million signing bonus. The 2011 NFL MVP’s 2014 cap number was originally $17.9 million. The signing bonus proration dropped from $7 million annually in Rodgers’ 2014-2017 contract years to $6.65 million because of insurance policy payments to the Packers relating to the quarterback missing seven games last season with a broken collarbone.

http://www.nationalfootballpost.com/...cap-kings.html
Didn't know they could insure the salary cap hit in that way. But, this raises a question: If an insurance payment allows you to gain back salary cap dollars, is the insurance premium for the policy a salary cap expense?