It is a four-year contract worth a reported $16 million, but as @RavensInsider reports, his per-year base salaries will be $1.25 million in 2014, $2.8 million in 2015, $3.65 million in 2016, and $4.35 million in 2017 along with a $4 million signing bonus.
This means his cap numbers will be $2.25 million in 2014, $3.8 million in 2015, $4.65 million in 2016 and $5.35 million in 2017.
Of his entire deal, $8 million is guaranteed.
What does this mean for the Lions? It gives Detroit a pretty decent out if Pettigrew's skills decline after the first two years of his contract. They would be almost all paid out of the guarantee at that point, so they could let him go if need be and not face a big loss in the monetary department. Also, remember that the salary cap is expected to jump massively over the next few seasons, so what looks like a big number for Pettigrew with the current cap might appear to be a bit smaller by the time 2016 comes around.
Pettigrew also offers a veteran option for a team without one at tight end. Other than Pettigrew, the tight ends on the Detroit roster have less than two seasons of combined actual game experience.