As of the census of 2000, there were 12,382 people, 4,968 households, and 3,293 families residing in the city. The population density was 1,845.5 people per square mile (712.5/km²). There were 5,239 housing units at an average density of 780.9/sq mi (301.5/km²). The racial makeup of the city was 97.71% White, 0.31% Black or African American, 0.28% Native American, 0.53% Asian, 0.01% Pacific Islander, 0.47% from other races, and 0.69% from two or more races. About 1.65% of the population were Hispanic or Latino of any race.
Approximately 30.7% of households had children under the age of 18 living with them, 54.7% were married couples living together, 8.3% had a female householder with no husband present, and 33.7% were non-families. Some 28.6% of all households were made up of individuals and 13.5% had someone living alone who was 65 years of age or older. The average household size was 2.40 and the average family size was 2.98.
In the city the population was spread out with 24.7% under the age of 18, 7.2% from 18 to 24, 29.5% from 25 to 44, 21.7% from 45 to 64, and 16.9% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 89.8 males. For every 100 females age 18 and over, there were 86.5 males.
The median income for a household in the city was $51,250, and the median income for a family was $62,950. Males had a median income of $42,683 versus $29,057 for females. The per capita income for the city was $25,716. About 0.8% of families and 1.6% of the population were below the poverty line, including 1.5% of those under age 18 and 3.3% of those age 65 or over.