William Lyon Homes is a regional homebuilder. The Company is engaged in the design, construction, marketing and sale of single-family detached and attached homes in California, Arizona, Nevada, Colorado, Washington and Oregon. The Company operates through six segments: California, Arizona, Nevada, Colorado, Washington and Oregon. The Company's California Segment consists of operations in Orange, Los Angeles, San Diego, Riverside, San Bernardino, Alameda, Contra Costa and San Joaquin counties. The Arizona Segment consists of operations in the Phoenix metropolitan area.