(CNN)Peyton Manning has informed the Denver Broncos that he will retire from the National Football League, according to the team's official website Sunday. The team's verified Twitter account said that the Broncos congratulate Manning for his "magnificent 18-year NFL career." No official news conference has been announced.

Though Broncos General Manager John Elway -- a man who, incidentally, retired from the Broncos after winning a Super Bowl himself (actually, two) -- had said there was no deadline for Manning to make his decision, it's a safe bet the team wanted its answer, if it didn't already have one, by March 9.

That's when the league's calendar year -- and thus, its free agency period -- begins, and if Manning had remained on the roster, the $19 million salary for his final contract year would have been guaranteed. That could have complicated negotiations with a host of free agents, including backup quarterback Brock Osweiler, who went 5-2 in Manning's absence last season.

If you're worried how the 39-year-old gunslinger will make ends meet, fear not (chuckle, chuckle), he's been moonlighting for years. According to Fortune magazine, Manning made $12.5 million from endorsements in 2014, which probably isn't surprising for a man who has served as a face for brands as big as Papa John's, Gatorade, Buick, Nationwide Insurance and DirecTV.

As a person and player, Manning's reputation has generally been considered beyond reproach, though two controversies surfaced or resurfaced this year: allegations that he used performance-enhancing drugs and that, as a student at the University of Tennessee, he sat on the face of a female trainer who was treating him.

He has vehemently denied the former, while downplaying the latter, saying he merely "mooned" a teammate in the trainer's presence -- "not exactly a criminal offense, but out of line."

Philanthropy awards

That said, he's received far more attention for his off-the-field philanthropy than for any alleged shenanigans. He and brother Eli, a quarterback for the New York Giants, helped the Red Cross deliver supplies to their hometown of New Orleans and other Gulf Coast locales after Hurricane Katrina. Last year, he received the Bart Starr Award for his charity work.

His PeyBack Foundation has raised more than $10 million for at-risk kids in Colorado, Indiana, Louisiana and Tennessee, and his philanthropic relationship with Indianapolis' St. Vincent Hospital prompted the medical center to rename its children's facility the Peyton Manning Children's Hospital in 2007.

NFL records

The five-time MVP is one of only two quarterbacks to beat every team in the NFL (Brett Favre is the other). He's the only quarterback to win Super Bowls with two teams, and he holds records for most career touchdown passes (539), most passing yards (71,940), most touchdowns in a season (55), most passing yards in a season (5,477), most wins (200) and most games with 300 or more yards passing (93), to name a few.

An iron man with deadly accuracy, Manning played every game of his first 13 seasons, until a neck injury sidelined him for all of 2011. The following year, the Indianapolis Colts, for whom Manning had played his entire career, drafted Stanford University quarterback Andrew Luck, and Manning headed west to the Mile High City.

There, he picked up where he had left off, playing every game for his first three seasons, while completing almost 68% of his passes and throwing for an average of at least 291 yards per game. He also threw 131 touchdowns in that time and set the record for most touchdowns in a season in 2013.

No national championship for the Vols

If there has been any gripe against Manning, it's that he's sometimes faltered when the lights were their brightest.

Despite helming four stellar University of Tennessee teams from 1994 to 1997, he neither beat the archrival Florida Gators nor skippered the Volunteers to a national championship in his college career. Doing either might have secured him a Heisman Trophy (Charles Woodson edged him out in 1997). It probably didn't help his case that his backup for two of those years, the arguably less talented Tee Martin, managed both feats after the Colts took Manning as the No. 1 overall pick in the NFL draft.

As a pro, he managed a 200-92 record, placing him atop an elite class that has only three members -- Favre at 199-123 and New England's Tom Brady at 194-60. Despite winning 68% of the games he played, lost in that statistic is a surprisingly inefficient playoff record of just 14-13.

It's perhaps fitting then that Manning snared his second Super Bowl after playing the worst football of his career. Not since his rookie season had Manning completed less than 60% of his passes, and his touchdown-to-interception ratio of 9-to-17 earned him a quarterback rating of 67.9, landing him 34th in the league.