Stephen Colbert Stephen Colbert

Stephen Colbert will officially sign off from Colbert Report on Thursday, Dec. 18, he announced during Thursday's broadcast.

"Stephen Colbert, the guy you've seen here for every night for nine years will be gone. All you'll have left of me is this book," he said, holding up his book America Again: Re-becoming Greatness We Never Weren't. "So pick up America Again in paperbook for a loved one. Or for a hated one."

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Colbert will take over for David Letterman as the new host of the Late Show sometime in 2015.

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