Judge Moon also ordered Humphries to pay restitution of $11.7 million.

Humphries began working as a teller for LFCU in 1988 but did not start stealing from it until 2000 when she began taking loans out in the names of members without their knowledge or authorization. She used the funds to help a friend and for her own benefit, according to federal prosecutors.

Humphries was able to make the loans without approval from Newcomb because they were small dollar amounts. She attempted to keep up with the payments but within six months fell behind, which is when Newcomb discovered the fraud.

Instead of firing Humphries or reporting her to the police, Newcomb said she would help Humphries solve the problem by creating even more bogus loans. Over the course of more than a decade, Humphries and Newcomb continued to pilfer the credit union through fake loans, loan participation agreements and check kiting, according to court documents.

The loan participation agreement led to a $1.6 million loss for the $17.9 million Northern Piedmont Federal Credit Union in Warrenton, Va.

Court documents also reveal that NCUA examiners had raised red flags about accounts at LFCU for several years.

"Specifically, going into the 2013 examination, NCUA examiners were concerned with the loan-to-share ratio, which was 133 – an extremely high number," Daniel P. Bubar, an assistant U.S. Attorney, wrote in a sentencing memorandum. "Another concerning indicator was that despite this outrageously large loan portfolio at LFCU, given the deposits at the facility, the default rate was very low. All of this signaled that something was amiss at LFCU and examiners were determined to identify what led to such seemingly outlying numbers."

NCUA examiners also found a host of other issues with the cooperative's loan portfolio such as misspelled names, similar handwriting in the loan files and missing loan documents.

When NCUA confronted Newcomb, she gave nonsensical answers or simply disavowed any knowledge of loan issues.

"One NCUA examiner even saw Newcomb change a loan term with a pen right in front of him, but without making any change in the computer system for that loan or giving any indication that she would contact the member about such a change to the loan's terms," Bubar wrote.

The false loans accounted for 88% of the loan portfolio at the time LFCU was liquidated by the NCUA in May 2013. The federal agency determined its loss due to the liquidation was $10 million.

"Ms. Humphries deeply regrets – and is ashamed of – her actions and certainly wishes that she had never started down this course of conduct," Allegra M.C. Black, an assistant federal public defender, wrote in a sentencing memorandum. "She especially regrets letting down the customer of Lynrocten, many of whom she considered friends.  "Her actions weighed heavily on her mind for many years, but she did not see a way out of the trouble she had caused."

Newcomb pleaded guilty March 6 to embezzlement, bank fraud and aggravated identity theft charges.