Singer-actress Katharine McPhee married producer Nick Cokas on Saturday in Beverly Hills, her rep Justin Gray Stone confirms exclusively to PEOPLE.

The 23-year-old American Idol season five runner-up and Cokas, 42, exchanged vows in a late afternoon ceremony at Beverly Hills Presbyterian Church.

“(Nick) is the love of my life,” McPhee gushed to PEOPLE. “This is a once in a lifetime occasion and everything is just perfect.”

McPhee wore a strapless ivory Manuel Mota gown and Neil Lane jewels (diamond and platinum chandelier earrings and diamond and platinum bracelets), while Cokas wore an Armani tuxedo. Fellow season five Idol contestants Kellie Pickler and Mandisa were among the 305 guests on hand for the nuptials.

McPhee and Cokas met in 2005 when they performed in a Los Angeles theater production of The Ghost and Mrs. Muir. Their union began as a friendship and blossomed when McPhee auditioned for American Idol later that year.

The two quietly got engaged last year when Cokas presented her with a custom-designed round brilliant cut platinum and diamond engagement ring.

McPhee recently wrapped filming the Anna Faris comedy I Know What Boys Like.