(CNN) -

John Dingell, the longest serving member of Congress in U.S. history, will announce Monday that he'll retire at the end of the year rather than run for re-election.

The 87-year-old Democratic congressman from Michigan told the Detroit News that "I'm not going to be carried out feet first," adding that "I don't want people to say I stayed too long."

Dingell told the Detroit News that his health "is good enough that I could have done it again. My doctor says I'm OK. And I'm still as smart and capable as anyone on the Hill." But Dingell went on to say that "I'm not certain I would have been able to serve out the two-year term."

Dingell added that the increased partisanship in the halls of Congress have diminished his love of his job.

"This is not the Congress I know and love," said Dingell. "It's hard for me to accept, but it's time to cash it in."

The retirement announcement from Dingell, the "dean of the House" for nearly two decades, was was confirmed to CNN by a Democratic source with knowledge of the congressman's thinking.

Dingell has served in the House of Representatives for 58 years. He was 29 when he was first elected to Congress in a special election to serve out the remainder of the term of his late father, who had held the seat since it was created in 1932.

Dingell's news comes amid a slew of retirement announcements from many senior House and Senate members from both parties. Michigan is also losing longtime Democratic Sen. Carl Levin, who has served in the chamber for 35 years.

Michigan's 12th Congressional District includes several working class southern suburbs of Detroit known as the "Downriver" area. The district stretches west to include Ann Arbor, home to the University of Michigan.

Dingell grabbed 68 percent of the vote in his 2012 re-election. And Barack Obama won two-thirds of the vote in the district in the 2008 and 2012 presidential elections.

There's speculation that Dingell's wife of 38 years, Debbie, a Democratic National Committee member, will run for her husband's seat.