As of the 2010 census, there were 18,383 people, 7,196 households, and 4,187 families residing in the City. The population density was 1,149.9 people per square mile (437.6/km²). There were 7,685 housing units at an average density of 614.8 per square mile (181.5/km²).
The racial makeup of the city was 70.4% white, 7.1% African American, 12.7% Native American, 0.7% Asian, 0.1% Pacific Islander, 2.1% from other races, and 6.9% from two or more races. Hispanic or Latino of any race was 6.5% of the population.
Of the 7,196 households, 22.1% had children under the age of 18 living with them, 46.6% were married couples living together, 13.7% had a female householder with no husband present, and 36.4% were non-families. 33.7% of all households were made up of individuals and 15.7% had someone living alone who was 65 years of age or older. The average household size was 2.16 and the average family size was 2.93.
In the City the population was spread out with 22.1% under the age of 18, 72.2% from 18 to 64, and 15.7% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 104.4 males.
The median income for a household in the city was $37,450, and the median income for a family was $36,480. Males had a median income of $31,637 versus $17,849 for females. The per capita income for the city was $20,406. About 16.1% of families and 17.3% of the population were below the poverty line, including 26.8% of those under age 18 and 11.6% of those aged 65 or over.