As of the 2010 United States Census, there were 862,477 people, 334,502 households, and 215,749 families residing in the county. The population density was . There were 362,004 housing units at an average density of . The racial makeup of the county was 74.8% white, 12.7% black or African American, 3.5% Asian, 0.3% American Indian, 6.0% from other races, and 2.6% from two or more races. Those of Hispanic or Latino origin made up 15.0% of the population. In terms of ancestry, 24.0% were Italian, 17.5% were Irish, 9.3% were German, 8.5% were English, 7.6% were Polish, and 2.0% were American.