An insufficient funds check was returned to your company. how does the bank treat this on your bank statement

A "bounced fund" or "bounced cheque" gets a fine for bank's account holder, so if someone gives you a cheque, you deposit it in your bank's account, and the bank tries to liquidate it and the other bank that's got the funds says, there isn't enough and therefore refuses to send anything, then your bank fines your account for the bouncing.
 
Depending on the bank could be more or less, in the US is more often than not about $20 or $25 for a bounced cheque.