Note 5 - Loans Receivable (Details) - Past Due and Nonaccrual Loans (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable	$ 1,055,117	$ 383,938
One-to-Four-Family Residential [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	4,966	3,511
Loans receivable, 90 days or more past due	3,545	1,664
Loans receivable, current	311,978	124,133
Loans receivable	320,489	129,308
One-to-Four-Family Residential [Member] | Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	1,121	637
Loans receivable, 90 days or more past due	2,572	1,664
Loans receivable, current	1,266	1,957
Loans receivable	4,959	4,258
Multifamily Residential [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, current	45,181	25,773
Loans receivable	45,181	25,773
Nonfarm Nonresidential [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	3,350	176
Loans receivable, 90 days or more past due	2,449	2,340
Loans receivable, current	364,175	166,386
Loans receivable	369,974	168,902
Nonfarm Nonresidential [Member] | Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	131
Loans receivable, 90 days or more past due	1,379	2,340
Loans receivable, current	1,603	1,717
Loans receivable	3,113	4,057
Farmland [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	15
Loans receivable, 90 days or more past due	628	666
Loans receivable, current	46,556	1,997
Loans receivable	47,199	2,663
Farmland [Member] | Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 90 days or more past due	628	666
Loans receivable, current	106	116
Loans receivable	734	782
Construction and Land Development [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	127	30
Loans receivable, 90 days or more past due	649	2,133
Loans receivable, current	97,818	21,728
Loans receivable	98,594	23,891
Construction and Land Development [Member] | Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 90 days or more past due	605	2,133
Loans receivable, current	19	334
Loans receivable	624	2,467
Commercial Loans [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	517
Loans receivable, 90 days or more past due	497	348
Loans receivable, current	138,857	28,685
Loans receivable	139,871	29,033
Commercial Loans [Member] | Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 90 days or more past due		348
Loans receivable, current	306	2
Loans receivable	306	350
Consumer Loans [Member] | Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	379
Loans receivable, 90 days or more past due	47	19
Loans receivable, current	33,383	4,349
Loans receivable	33,809	4,368
Consumer Loans [Member] | Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	5
Loans receivable, 90 days or more past due	14	19
Loans receivable, current	15	5
Loans receivable	34	24
Gross of Undisbursed Funds, Unearned Discounts and Net Loan Fees, and Allowance for Loan and Lease Losses [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	9,354	3,717
Loans receivable, 90 days or more past due	7,815	7,170
Loans receivable, current	1,037,948	373,051
Loans receivable	1,055,117	383,938
Nonaccrual [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans receivable, 30-89 days past due	1,257	637
Loans receivable, 90 days or more past due	5,198	7,170
Loans receivable, current	3,315	4,131
Loans receivable	$ 9,770	$ 11,938