Update 1:45 p.m. -- I did not factor in veteran's minimum salary cap offsets. Simply put, veteran minimum salaries escalate by the number of seasons the player accrues, but the NFL collective bargaining agreement has a provision that allows veterans to count against the cap only as a two-year player if they sign a veteran's minimum deal with no additional incentives or bonuses.

This means the Lions should have some additional money, potentially up to $905,000.

The Detroit Lions have been busy in free agency. Aided largely by the restructuring of defensive tackle Ndamukong Suh's contract, the team has been able to go on a spending spree of sorts.

When free agency opened, Detroit had less than $2 million to spend. Suh's restructure, which lowered his base salary from $12.15 million to $630,000, cleared $7.7 million in cap space for the Lions.

The bad news is Suh's cap number for 2014 is now more than $21 million, but that's a topic for another day.

Detroit used the additional funds created by Suh's restructuring to re-sign DeAndre Levy, Chris Houston, Kassim Osgood, Amari Spievey and Don Muhlbach, as well as add Reggie Bush, Glover Quin and Jason Jones.

In all, the Lions' front office did an excellent job negotiating reasonable contracts, particularly the 2013 cap numbers. Houston's $2.3 million figure was the highest of the bunch.

Detroit had another $2.75 million come off the books on Thursday when offensive tackle Jeff Backus decided to call it a career.

With all factors taken into consideration, the Lions' top 51 cap numbers, added to the dead money from previous cuts, comes in right around $119.5 million. Given that the cap is $123 million and the Lions had a $466,000 carryover from last year, the team currently has approximately $4 million in space with available avenues to clear even more if needed.

The only thing we know that certainly remains on the to-do list is re-signing kicker Jason Hanson. That eventual deal shouldn't eat up too much space, especially since only the top 51 salaries count against the cap, meaning each new signing is offset by a lower cap number dropping from the calculation. Currently, that would be Kellen Moore's $486,666.

Now, an obvious question is how much will the Lions need to sign their draft picks. Eventually, the team will need between $3-4 million, most of which is reserved for the first-round selection. The good news is rookies count just $405,000 each until they officially sign contracts. Detroit likely won't even need to worry about it until July, which is plenty of time to work out an extension for quarterback Matthew Stafford.

Regarding Stafford's extension, it's not a pressing issue. In fact, when it does get done, the Lions no longer have to worry about drastically reducing his $20.8 million cap number in 2013. Sure, it will still be trimmed, but reducing the 2014 and 2015 cap figures will likely be the bigger reward.

So what does all this mean?

It means the Lions can still be buyers on the market, whether it's re-signing safety Louis Delmas or pursuing another team's unrestricted free agent.

It's even possible, given the market, the Lions could make a run at Elvis Dumervil if the defensive end is cut by the Broncos.

A final option would be playing it slow, given the team has already addressed several needs. The Lions could save the money and go bargain shopping during the second wave of cuts after the draft.

Regardless, the Lions definitely aren't done adding pieces this offseason.