As of the 2010 United States Census, there were 169,572 people, 65,104 households, and 40,124 families residing in the county. The population density was . There were 69,656 housing units at an average density of . The racial makeup of the county was 84.3% white, 7.3% black or African American, 4.3% Asian, 0.2% American Indian, 1.5% from other races, and 2.3% from two or more races. Those of Hispanic or Latino origin made up 4.4% of the population. In terms of ancestry, 31.2% were German, 15.4% were Irish, 11.4% were American, and 11.0% were English.