Answer by taking a quote from the following article:

Frasier Winslow Crane is a fictional character on the American television sitcoms Cheers and Frasier, portrayed by Kelsey Grammer. Grammer received award recognitions for portraying this character in these two shows, in addition to a 1992 one-time appearance in Wings. The character debuts in the Cheers third-season premiere, "Rebound (Part 1)" (1984), as Diane Chambers's love interest, part of the Sam and Diane story arc. Intended to appear for only a few episodes, Grammer's performance for the role was praised by producers, prompting them to expand his role and to increase his prominence.

During the course of the spin-off's run, especially in scenes at Frasier's apartment, Frasier and Martin regularly argue over the living arrangements and each other's personalities: Frasier is sophisticated, intellectual, and erudite, while Martin is a rugged man of simple tastes who speaks (according to Frasier) in words that no "sophisticated, educated" person could understand. While Frasier has many common interests with Niles and shares adventures (or misadventures) with him, he has little in common with his father, Martin.  In "Dinner at Eight" (1993), Martin takes Frasier and Niles to a themed steakhouse, where health-conscious, snobby Frasier and Niles criticize the food, the restaurant's customs, and the clientele. Martin becomes frustrated and angry before leaving, remarking upon departing that their mother, Hester, would be disappointed with their behavior. Frasier and Niles try to prove that they are not "snobs" by finishing their meal, although it takes them until after closing time. Ironically, in the Cheers season seven episode, "I Kid You Not" (1988), Frasier invites Carla and her son Ludlow to the upper class, expensive restaurant, but Carla and Ludlow criticize and mock it, enraging Frasier.  In "Chess Pains", Frasier teaches Martin how to play chess, but is horrified when Martin becomes a better player than him, due to Martin's seasoned insight as a police detective. Frasier becomes obsessed with winning against his father until Frasier wins one match and Martin does not want to play with Frasier anymore. One late night, Frasier wakes Martin up and asks him whether he lost the chess match on purpose. Martin responds that Frasier "won, fair and square" and nothing more.  In an episode of the seventh season "A Tsar Is Born" (1999), Martin takes an old family clock, which Frasier and Niles consider hideous, to exhibit on the television show Antiques Roadshow. As the boys soon discover, the clock is related to their ancestors and royalty, and may be worth a fortune, and heightens their expectations of being descended from royalty. Unfortunately, when they try to sell the clock later, the brothers learn from an antique specialist that it was stolen from the daughter of Tsar Alexander II. Moreover, their great-great-grandmother was discovered to have been the clock thief and the daughter's scullery maid, and is discovered to have later been a prostitute in New York City. Therefore, the brothers are left without a fortune, a clock, and their royal dreams are crushed, as Frasier puts it, they are descended from "thieves and whores". Much to their anger, Martin buys a Winnebago RV with money Frasier claimed were the proceeds from selling the clock.

What did Fraisers father do for a living?