In your state, quite long. They can commence prosecution up to three years from the date the crime occurred. Frankly, if you didn't hear about in within a couple of months of it happening, it likely isn't going to.
Guidance:
1. Stop stealing.
2. Stay out of that Target for a while, they may be watching for you.
3. If the police or prosecutor come asking questions, decline to speak to them without an attorney.
4. If you get arrested or notice of criminal charges, do nothing/say nothing before you get an attorney.

