(CNN) A senator is asking the Treasury Department to turn over records of a lucrative real estate sale Donald Trump made to a Russian billionaire as the Senate Finance Committee looks into Trump's ties to Russians.

Sen. Ron Wyden, the committee's ranking member, on Friday requested the financial records of the sale of Trump's former estate in Palm Beach to Dmitry Rybolovlev.

Wyden's letter outlined how Donald Trump bought a 6.3-acre property in Florida for $41.35 million in 2004 and then sold that property to a company owned by the businessman four years later. The sale price to Rybolovlev more than doubled Trump's initial investment, to $95 million. The property's appraisal in 2008 fell short of that sale price by $30 million, Wyden said.

"In the context of the President's then-precarious financial position, I believe that the Palm Beach property sale warrants further scrutiny," the Oregon Democrat wrote. "It is imperative that Congress follow the money and conduct a thorough investigation into any potential money laundering or other illicit financial dealings between the President, his associates, and Russia."

As ranking member, Wyden has the right to ask for these documents, and some of his past efforts to receive Trump-related records from Treasury have produced results. Still, Wyden's letter doesn't carry the weight of a bipartisan request or one from the majority. Republicans on Capitol Hill have shown little interest in investigating Trump's finances.

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