PITTSFIELD -- A 48-year-old Pittsfield woman will spend the next three years in jail after pleading guilty to taking $200,000 from the Greylock Federal Credit Union when she was employed there.

Janine Shepard pleaded guilty in Berkshire Superior Court on Wednesday to one count of larceny over $250 and one count of making false entries into corporate books.

Superior Court Judge John A. Agostini ordered Shepard to serve a total of three years in the Berkshire County House of Correction -- two years on the larceny charge, followed by a one-year sentence for making false entries into corporate books.

Shepard, who had been a teller supervisor for Greylock at its branch on Merrill Road, took $200,000 while employed by the credit union between Jan. 1, 2010 and Feb. 18, 2012.

She had been employed at Greylock for 13 years, but both she and a co-worker were fired shortly after the credit union uncovered the situation, and reported it to law enforcement authorities, according to President and CEO Marilyn Sperling.

The investigation was conducted by state police detectives assigned to the Berkshire District Attorney's Office.

Sperling said Shepard allegedly falsified documents at Greylock while she gradually took money from available cash, then "manipulated" and "lied" to another employee who was responsible for checking her work. The incident prompted Greylock to change its security procedures.