When you think of a bank robbery, you probably imagine some heavily armed crew trying to run off with as much money as possible in a very short window of time. But one Texas bank employee almost managed to get away with stealing more than $1 million, by chiseling away at her employer over the course of a decade.

A former First National Bank employee pleaded guilty this week to falsifying bank records to conceal the fact that she pilfered more than $1.25 million from the financial institution.

According to the Justice Department, the woman’s position as a teller supervisor gave her responsibility for verifying and recording the amount of money in the bank’s cash vaults. She allegedly used this authority to conceal that each month — from June 2004 to June 2014 — she took about $10,000 from the bank.

The woman admitted to creating fraudulent entries in bank records in order to conceal the theft of $1.25 million.

The scheme, the U.S. Attorney reports, was uncovered in June 2014 when PlainsCapital Bank acquired the Edinburg, TX, location of First National Bank where the woman worked.

A judge accepted the former employee’s plea. She now faces up to 30 years in federal prison, as well as a $1 million fine. Her sentencing is scheduled for April 26.