Stock-Based Compensation (Details) (USD $)	3 Months Ended	9 Months Ended			9 Months Ended						1 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Sep. 30, 2010	May 31, 2008	Sep. 30, 2011 Restricted Stock Awards [Member]	Sep. 30, 2010 Restricted Stock Awards [Member]	Sep. 30, 2011 Restricted Stock Units [Member]	Sep. 30, 2010 Restricted Stock Units [Member]	Sep. 30, 2011 Stock Options [Member]	Sep. 30, 2010 Stock Options [Member]	Jan. 31, 2011 Old National Bancorp [Member]	Jan. 31, 2011 Monroe Bancorp [Member]
Shares authorized under incentive compensation plan				1,000,000
Shares available for issuance		2,500,000
Stock based compensation expense		$ 2,551,000	$ 1,702,000						$ 61,000	$ 119,000
Options for shares converted on acquisition												300,000
Options for shares received on acquisition											300,000
Restricted stock awards granted					121,000
Unrecognized compensation expense					1,700,000
Restricted stock expense					700,000	600,000	800,000	300,000
Reversal of expense related to performance based restricted stock grants	$ 100,000					$ 100,000	$ 13,000	$ 200,000
Restricted stock units granted							159,000
Restricted stock issued	10,000