There are lots of ways that thieves can gain access to your bank account info offline as well. Here are a few precautions for you to take:

As with online banking, pay attention. Don't just get your bank statement and toss it on the 'to-do' pile on your desk. Your to-do pile is probably way too big, and it might be days before you get around to opening that envelope. You can't spot a problem if you're not paying attention -- and if you don't spot an existing problem, it could cost you a great deal.
Action: Read your bank statements as soon as you get them.

Be very careful with your ATM/Debit card. Don't lend your ATM/Debit card to anyone or share your PIN. And never write your PIN number on your ATM/Debit card or have it anywhere near your ATM/Debit card (in the event that your wallet gets stolen).

Shield your transactions when you use your ATM/Debit card so no one can see what you are keying in. Check to make sure that no hardware devices have been added to an ATM machine you're using. These devices, called 'Skimmer' devices, can record the info from the magnetic strip on your ATM/Debit card along with your PIN number. They take less than 15 seconds for the scammer to install and uninstall them. Some Skimmer devices are installed over the keypad on an ATM machine -- and may include warnings, supposedly from the bank, about how this equipment is being tested. If you see anything like this, do NOT use the ATM machine.

Shred old and unused checks, as well as any unwanted paper that has your bank account number on it. - Never give anyone a signed blank check.