Note 3 - Securities (Detail) - Securities In An Unrealized Loss Position (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
US Government Corporations and Agencies Securities [Member]
Number of Securities	2	4
Fair Value - Less Than 12 Months		$ 9,096
Unrealized Losses - Less Than 12 Months		120
Fair Value - 12 Months or Longer	5,035
Unrealized Losses - 12 Months or Longer	25	1
Fair Value - Total	5,035	9,096
Unrealized Losses - Total	25	121
Collateralized Residential Mortgage Obligations [Member]
Number of Securities	30	19
Fair Value - Less Than 12 Months	163,819	131,056
Unrealized Losses - Less Than 12 Months	1,818	1,727
Fair Value - 12 Months or Longer	12,628	7,843
Unrealized Losses - 12 Months or Longer	528	637
Fair Value - Total	176,447	138,899
Unrealized Losses - Total	2,346	2,364
Other Residential Mortgage-Backed Securities [Member]
Number of Securities	4	5
Fair Value - Less Than 12 Months	182	6,084
Unrealized Losses - Less Than 12 Months	17	51
Fair Value - 12 Months or Longer	1,072	159
Unrealized Losses - 12 Months or Longer	6	10
Fair Value - Total	1,254	6,243
Unrealized Losses - Total	23	61
State and Municipal [Member]
Number of Securities	19	479
Fair Value - Less Than 12 Months	934	99,537
Unrealized Losses - Less Than 12 Months	2	3,142
Fair Value - 12 Months or Longer	7,857	166,403
Unrealized Losses - 12 Months or Longer	364	9,658
Fair Value - Total	8,791	265,940
Unrealized Losses - Total	366	12,800
Collateralized Debt Obligations [Member]
Number of Securities	6	6
Fair Value - 12 Months or Longer	13,394	14,858
Unrealized Losses - 12 Months or Longer	35,365	34,837
Fair Value - Total	13,394	14,858
Unrealized Losses - Total	35,365	34,837
Corporate Debt [Member]
Number of Securities	1
Fair Value - Less Than 12 Months	2,157
Unrealized Losses - Less Than 12 Months	11
Fair Value - Total	2,157
Unrealized Losses - Total	11
Unrealized Loss Position [Member]
Number of Securities	62	513
Fair Value - Less Than 12 Months	167,092	245,773
Unrealized Losses - Less Than 12 Months	1,848	5,040
Fair Value - 12 Months or Longer	39,986	189,263
Unrealized Losses - 12 Months or Longer	36,288	45,143
Fair Value - Total	207,078	435,036
Unrealized Losses - Total	$ 38,136	$ 50,183