WASHINGTON — The public will soon get its first look at a voluminous report on the C.I.A.’s detention and interrogation practices during the George W. Bush administration, after the Senate Intelligence Committee voted on Thursday to declassify key sections of it.

“The report exposes brutality that stands in stark contrast to our values as a nation,” Senator Dianne Feinstein, a Democrat of California and the chairwoman of the committee, said in a written statement after the vote.

It continued, “This is not what Americans do.”

The committee voted to declassify the report’s executive summary and conclusions — more than 500 of its 6,200 pages. The next step is President Obama’s approval. Mr. Obama, who opposed the C.I.A. program as a presidential candidate and discontinued it once he took office in 2009, has said he wants the findings of the report made public.

The White House would not say how long it would take the administration to review the report for sensitive national security disclosures, but a spokeswoman said the process, which will include a review by the C.I.A., would be expedited.