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Note 8 - Deposits (Tables) | 12 Months Ended
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Dec. 31, 2014
Disclosure Text Block [Abstract] |
Summary of Deposits and Percentage Change in Deposits [Table Text Block] |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Percent |
|  | December 31, 2014 |  |  | December 31, 2013 |  |  | Increase |
|  | Balance |  |  | % |  |  | Balance |  |  | % |  |  | (Decrease) |
Noninterest-bearing demand |  | $ | 558,738,000 |  |  |  | 24.5 | % |  | $ | 224,580,000 |  |  |  | 20.1 | % |  |  | 148.8 | %
Interest-bearing checking |  |  | 413,382,000 |  |  |  | 18.2 |  |  |  | 197,388,000 |  |  |  | 17.6 |  |  |  | 109.4 |
Money market |  |  | 235,587,000 |  |  |  | 10.3 |  |  |  | 133,369,000 |  |  |  | 11.9 |  |  |  | 76.6 |
Savings |  |  | 330,459,000 |  |  |  | 14.5 |  |  |  | 52,606,000 |  |  |  | 4.7 |  |  |  | 528.2 |
Time, under $100,000 |  |  | 181,026,000 |  |  |  | 8.0 |  |  |  | 43,251,000 |  |  |  | 3.9 |  |  |  | 318.5 |
Time, $100,000 and over |  |  | 382,120,000 |  |  |  | 16.8 |  |  |  | 254,600,000 |  |  |  | 22.8 |  |  |  | 50.1 |
|  |  | 2,101,312,000 |  |  |  | 92.3 |  |  |  | 905,794,000 |  |  |  | 81.0 |  |  |  | 132.0 |
Out-of-area time, under $100,000 |  |  | 2,422,000 |  |  |  | 0.1 |  |  |  | 4,078,000 |  |  |  | 0.4 |  |  |  | (40.6 | )
Out-of-area time, $100,000 and over |  |  | 173,181,000 |  |  |  | 7.6 |  |  |  | 209,039,000 |  |  |  | 18.6 |  |  |  | (17.2 | )
|  |  | 175,603,000 |  |  |  | 7.7 |  |  |  | 213,117,000 |  |  |  | 19.0 |  |  |  | (17.6 | )
Total deposits |  | $ | 2,276,915,000 |  |  |  | 100.0 | % |  | $ | 1,118,911,000 |  |  |  | 100.0 | % |  |  | 103.5 |
ContractualMaturities of Certificates of Deposits [Table Text Block] |
|  | 2014 |  |  | 2013 |
In one year or less |  | $ | 368,163,000 |  |  | $ | 213,454,000 |
In one to two years |  |  | 153,346,000 |  |  |  | 80,138,000 |
In two to three years |  |  | 118,919,000 |  |  |  | 73,271,000 |
In three to four years |  |  | 60,953,000 |  |  |  | 95,979,000 |
In four to five years |  |  | 37,368,000 |  |  |  | 48,126,000 |
Total certificates of deposit |  | $ | 738,749,000 |  |  | $ | 510,968,000 |
Contractual Maturities of Certificates of Deposits of More Than Specified Amount [Table Text Block] |
|  | 2014 |  |  | 2013 |
Up to three months |  | $ | 75,356,000 |  |  | $ | 57,469,000 |
Three months to six months |  |  | 65,838,000 |  |  |  | 41,237,000 |
Six months to twelve months |  |  | 125,492,000 |  |  |  | 93,920,000 |
Over twelve months |  |  | 288,615,000 |  |  |  | 271,013,000 |
Total certificates of deposit |  | $ | 555,301,000 |  |  | $ | 463,639,000 |

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