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Note 8 - Deposits (Tables) | 12 Months Ended
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Dec. 31, 2015
Disclosure Text Block [Abstract] |
Summary of Deposits and Percentage Change in Deposits [Table Text Block] |
|  | December 31, 2015 |  |  | December 31, 2014 |  |  | Percent Increase |
|  | Balance |  |  | % |  |  | Balance |  |  | % |  |  | (Decrease) |
Noninterest-bearing demand |  | $ | 674,568,000 |  |  |  | 29.6 | % |  | $ | 558,738,000 |  |  |  | 24.5 | % |  |  | 20.7 | %
Interest-bearing checking |  |  | 403,354,000 |  |  |  | 17.7 |  |  |  | 413,382,000 |  |  |  | 18.2 |  |  |  | (2.4 | )
Money market |  |  | 274,395,000 |  |  |  | 12.1 |  |  |  | 235,587,000 |  |  |  | 10.3 |  |  |  | 16.5 |
Savings |  |  | 332,794,000 |  |  |  | 14.6 |  |  |  | 330,459,000 |  |  |  | 14.5 |  |  |  | 0.7 |
Time, under $100,000 |  |  | 155,655,000 |  |  |  | 6.9 |  |  |  | 181,026,000 |  |  |  | 8.0 |  |  |  | (14.0 | )
Time, $100,000 and over |  |  | 313,247,000 |  |  |  | 13.8 |  |  |  | 382,120,000 |  |  |  | 16.8 |  |  |  | (18.0 | )
|  |  | 2,154,013,000 |  |  |  | 94.7 |  |  |  | 2,101,312,000 |  |  |  | 92.3 |  |  |  | 2.5 |
Out-of-area time, under $100,000 |  |  | 149,000 |  |  | < 0.1 |  |  |  | 2,422,000 |  |  |  | 0.1 |  |  | NM |
Out-of-area time, $100,000 and over |  |  | 121,220,000 |  |  |  | 5.3 |  |  |  | 173,181,000 |  |  |  | 7.6 |  |  |  | (30.0 | )
|  |  | 121,369,000 |  |  |  | 5.3 |  |  |  | 175,603,000 |  |  |  | 7.7 |  |  |  | (30.9 | )
Total deposits |  | $ | 2,275,382,000 |  |  |  | 100.0 | % |  | $ | 2,276,915,000 |  |  |  | 100.0 | % |  |  | (0.1% | )
Contractual Maturities Of Certificates Of Deposits [Table Text Block] |
|  | 2015 |  |  | 2014 |
In one year or less |  | $ | 305,122,000 |  |  | $ | 368,163,000 |
In one to two years |  |  | 145,775,000 |  |  |  | 153,346,000 |
In two to three years |  |  | 71,988,000 |  |  |  | 118,919,000 |
In three to four years |  |  | 37,527,000 |  |  |  | 60,953,000 |
In four to five years |  |  | 29,859,000 |  |  |  | 37,368,000 |
Total certificates of deposit |  | $ | 590,271,000 |  |  | $ | 738,749,000 |
Contractual Maturities Of Certificates Of Deposits Of More Than Specified Amount [Table Text Block] |
|  | 2015 |  |  | 2014 |
Up to three months |  | $ | 73,783,000 |  |  | $ | 75,356,000 |
Three months to six months |  |  | 50,375,000 |  |  |  | 65,838,000 |
Six months to twelve months |  |  | 91,786,000 |  |  |  | 125,492,000 |
Over twelve months |  |  | 218,523,000 |  |  |  | 288,615,000 |
Total certificates of deposit |  | $ | 434,467,000 |  |  | $ | 555,301,000 |

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