Loans (Details) (USD $)	3 Months Ended
	Mar. 31, 2013 item mi	Dec. 31, 2012	Mar. 31, 2013 Illinois	Dec. 31, 2012 Illinois	Mar. 31, 2013 Florida	Dec. 31, 2012 Florida	Mar. 31, 2012 Florida	Dec. 31, 2011 Florida	Mar. 31, 2013 Indiana	Dec. 31, 2012 Indiana	Mar. 31, 2013 Commercial	Dec. 31, 2012 Commercial	Mar. 31, 2013 Commercial Illinois	Dec. 31, 2012 Commercial Illinois	Mar. 31, 2013 Commercial Florida	Dec. 31, 2012 Commercial Florida	Mar. 31, 2012 Commercial Florida	Dec. 31, 2011 Commercial Florida	Mar. 31, 2013 Commercial Indiana	Dec. 31, 2012 Commercial Indiana	Mar. 31, 2013 Commercial real estate	Dec. 31, 2012 Commercial real estate	Mar. 31, 2013 Commercial real estate Illinois	Dec. 31, 2012 Commercial real estate Illinois	Mar. 31, 2013 Commercial real estate Florida	Dec. 31, 2012 Commercial real estate Florida	Mar. 31, 2012 Commercial real estate Florida	Dec. 31, 2011 Commercial real estate Florida	Mar. 31, 2013 Commercial real estate Indiana	Dec. 31, 2012 Commercial real estate Indiana	Mar. 31, 2013 Real estate construction	Dec. 31, 2012 Real estate construction	Mar. 31, 2013 Real estate construction Illinois	Dec. 31, 2012 Real estate construction Illinois	Mar. 31, 2013 Real estate construction Florida	Dec. 31, 2012 Real estate construction Florida	Mar. 31, 2012 Real estate construction Florida	Dec. 31, 2011 Real estate construction Florida	Mar. 31, 2013 Real estate construction Indiana	Dec. 31, 2012 Real estate construction Indiana	Mar. 31, 2013 Retail real estate	Dec. 31, 2012 Retail real estate	Mar. 31, 2013 Retail real estate Illinois	Dec. 31, 2012 Retail real estate Illinois	Mar. 31, 2013 Retail real estate Florida	Dec. 31, 2012 Retail real estate Florida	Mar. 31, 2012 Retail real estate Florida	Dec. 31, 2011 Retail real estate Florida	Mar. 31, 2013 Retail real estate Indiana	Dec. 31, 2012 Retail real estate Indiana	Mar. 31, 2013 Retail other	Dec. 31, 2012 Retail other	Mar. 31, 2013 Retail other Illinois	Dec. 31, 2012 Retail other Illinois	Mar. 31, 2013 Retail other Florida	Dec. 31, 2012 Retail other Florida	Mar. 31, 2012 Retail other Florida	Dec. 31, 2011 Retail other Florida	Mar. 31, 2013 Retail other Indiana	Dec. 31, 2012 Retail other Indiana
Loans
Total	$ 2,060,680,000	$ 2,073,110,000	$ 1,672,575,000	$ 1,691,946,000	$ 284,152,000	$ 277,464,000			$ 103,953,000	$ 103,700,000	$ 425,922,000	$ 433,688,000	$ 392,171,000	$ 399,300,000	$ 11,959,000	$ 10,861,000			$ 21,792,000	$ 23,527,000	$ 992,969,000	$ 981,132,000	$ 776,674,000	$ 777,752,000	$ 147,501,000	$ 138,170,000			$ 68,794,000	$ 65,210,000	$ 89,178,000	$ 86,101,000	$ 69,263,000	$ 67,152,000	$ 17,040,000	$ 15,972,000			$ 2,875,000	$ 2,977,000	$ 539,427,000	$ 559,836,000	$ 421,790,000	$ 435,911,000	$ 107,254,000	$ 112,052,000			$ 10,383,000	$ 11,873,000	$ 13,184,000	$ 12,353,000	$ 12,677,000	$ 11,831,000	$ 398,000	$ 409,000			$ 109,000	$ 113,000
Less held for sale	30,833,000	40,003,000
Total loans before allowance for loan losses	2,029,847,000	2,033,107,000			282,630,000	275,182,000									11,959,000	10,861,000									147,501,000	138,170,000									17,040,000	15,972,000									105,732,000	109,770,000									398,000	409,000
Less allowance for loan losses	47,773,000	48,012,000			15,049,000	15,433,000	18,975,000	19,469,000							1,485,000	1,437,000	1,741,000	1,939,000							6,106,000	6,062,000	8,277,000	8,413,000							2,326,000	2,315,000	2,540,000	2,936,000							5,128,000	5,614,000	6,405,000	6,160,000							4,000	5,000	12,000	21,000
Net loans	1,982,074,000	1,985,095,000
Net deferred loan origination costs	700,000	800,000
Minimum target period for lending via intermediate term loans	0 years
Maximum target period for lending via intermediate term loans	7 years
Geographical area from lending offices which attempt is made to lend short and intermediate term loans (in miles)	125
Direct and indirect maximum total borrowing relationship limit	20,000,000
Borrowing relationships, threshold above which board of directors will review annually	$ 20,000,000
Number of primary areas for lending loan	5