According to the U.S. Census Bureau, the county has a total area of 1,998 square miles (5,170 km2), of which 1,971 square miles (5,100 km2) is land and 27 square miles (70 km2) (1.3%) is water. Native vegetation based on NRCS soils information shows: 
There were 12,070 households out of which 32.30% had children under the age of 18 living with them, 54.90% were married couples living together, 8.50% had a female householder with no husband present, and 33.30% were non-families. 28.90% of all households were made up of individuals and 13.80% had someone living alone who was 65 years of age or older. The average household size was 2.47 and the average family size was 3.07.
In the county the population was spread out with 25.90% under the age of 18, 9.70% from 18 to 24, 24.80% from 25 to 44, 22.20% from 45 to 64, and 17.40% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 98.10 males. For every 100 females age 18 and over, there were 95.50 males.
The median income for a household in the county was $35,105, and the median income for a family was $44,310. Males had a median income of $31,472 versus $21,535 for females. The per capita income for the county was $17,279. About 7.30% of families and 10.90% of the population were below the poverty line, including 13.30% of those under age 18 and 10.90% of those age 65 or over.