No clue, haven't been following it closely.
I would imagine he wants to be one of the highest, if not the highest, paid defensive players in all of football.
http://www.spotrac.com/rankings/nfl/average/defense/limit-25/
Average Salaries - Defensive Players
1. Mario Williams - $16MM
2. Clay Matthews - $13.2MM
3. Greg Hardy - $13.116MM (Franchise tag)
4. Ndamukong Suh - $12.7MM
Clay Matthews signed 5 years, $66MM w/$20.5MM guaranteed
Mario Williams signed 6 years, $96MM w/$24.9MM guaranteed
He'll probably be in that ballpark if the Lions re-sign him, with cap relief in the earlier years (when Staff/CJ cap numbers go up) and cap heavy numbers in the later years.