Former U.S. Speaker of the House Dennis Hastert leaves the Dirksen Federal courthouse after his sentencing hearing in Chicago, Illinois, United States April 27, 2016. REUTERS/Frank Polich/File Photo

CHICAGO (Reuters) - Former U.S. House of Representatives Speaker Dennis Hastert is due to report to federal prison on Wednesday to serve a 15-month sentence for a financial crime linked to sexual abuse of wrestlers he coached in the 1960s and 1970s, according to court documents.

Hastert, once a revered figure in Illinois politics, will serve his sentence at the Federal Medical Center in Rochester, Minnesota, said two sources with knowledge of the case, who declined to be named.

The media office at the Federal Bureau of Prisons was not immediately available for comment.

U.S. District Judge Thomas Durkin sentenced Hastert, 74, to 15 months in prison, but the time could be reduced for good behavior. Durkin said he would have given him a longer sentence if it had not been for Hastert’s age and poor health.

Hastert, the longest-serving Republican House speaker in history, pleaded guilty last year to the crime of structuring, which involves withdrawing a large sum of money in small increments to avoid detection.

Hastert was taking the money out of his bank accounts to pay a promised $3.5 million in compensation for pain and suffering to one of his five sexual abuse victims, he admitted in his plea agreement and at his sentencing hearing.

Hastert has not been charged with or convicted of sex abuse due to the statute of limitations, but at his sentencing hearing in April, he admitted to sexual abuse of boys when he was a high school teacher and coach in his hometown of Yorkville, Illinois.

The Federal Medical Center has a total of 678 inmates and is designed for male prisoners who need special medical care, according to its website. Hastert nearly died last year after suffering a stroke and being treated for a severe blood infection and undergoing surgery for a spinal infection, his lawyers said in court filings last year.