In Illinois, banks can exercise the right of setoff only against deposit accounts held at the bank, and only if certain requirements are met: either (1) the deposit contract allows for a right of setoff or the deposit accounts are owned by the same party (or parties) that owe the debt, and (2) the debt has matured. Selby v. DuQuoin State Bank, 223 Ill.App.3d 105, 107 (5th Dist. 1991) (the right of setoff allows a bank to “apply its depositor’s account for a debt he owes to the bank”); Fisher v. State Bank of Annawan, 163 Ill.2d 177, 181 (1994).