Goodwill and Other Intangibles Assets (Details) (USD $)			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2009 Busey Bank	Dec. 31, 2009 Busey Bank Parent	Dec. 31, 2012 FirsTech	Dec. 31, 2011 FirsTech	Dec. 31, 2012 Busey Wealth Management	Dec. 31, 2011 Busey Wealth Management
Goodwill and Other Intangibles Assets
Goodwill impairment			$ 208,200,000	$ 3,400,000
Total Goodwill	$ 20,686,000	$ 20,686,000			$ 8,992,000	$ 8,992,000	$ 11,694,000	$ 11,694,000