Note 19 - Fair Value of Financial Instruments (Details) - Estimated Fair Values of Financial Instruments (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
FINANCIAL ASSETS:
Cash and cash equivalents	$ 113,086	$ 23,970	$ 42,607
Interest-bearing time deposits in banks	87,115us-gaap_InterestBearingDepositsInBanks	17,728us-gaap_InterestBearingDepositsInBanks
Other investment securities	5,864bsf_OtherInvestmentSecurities	457bsf_OtherInvestmentSecurities
Loans held for sale	6,409us-gaap_LoansReceivableHeldForSaleNet	4,205us-gaap_LoansReceivableHeldForSaleNet
Accrued interest receivable	4,485us-gaap_InterestReceivable	1,473us-gaap_InterestReceivable
Loans receivable—net	1,041,222	371,149
FINANCIAL LIABILITIES:
Short term borrowings	12,083us-gaap_ShortTermBorrowings
Other borrowings	61,258us-gaap_OtherBorrowings	5,941us-gaap_OtherBorrowings
Fair Value, Inputs, Level 1 [Member]
FINANCIAL ASSETS:
Cash and cash equivalents	113,086	23,970
Cash and cash equivalents	113,086	23,970
FINANCIAL LIABILITIES:
Short term borrowings	12,083
Short term borrowings	12,083
Fair Value, Inputs, Level 2 [Member]
FINANCIAL ASSETS:
Interest-bearing time deposits in banks	12,421	24,118
Interest-bearing time deposits in banks	12,663	24,573
Other investment securities	5,864	457
Other investment securities	5,864	457
Loans held for sale	6,409	4,205
Loans held for sale	6,409	4,205
Cash surrender value of life insurance	44,130	23,811
Cash surrender value of life insurance	44,130	23,811
Accrued interest receivable	4,485	1,473
FINANCIAL LIABILITIES:
Checking, money market and savings accounts	800,203	203,067
Other borrowings	61,258	5,941
Other borrowings	62,175	6,017
Accrued interest payable	304	33
Fair Value, Inputs, Level 3 [Member]
FINANCIAL ASSETS:
Loans receivable—net	1,041,222	371,149
Loans receivable—net	1,063,529	377,851
FINANCIAL LIABILITIES:
Certificates of deposit	463,594	266,658
Certificates of deposit	$ 464,650	$ 266,495

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Fair value of Interest-bearing deposits in other financial institutions including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Other security investments represent stocks that do not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). These stocks include but are not limited to Federal Home Loan Bank (FHLB) and Federal Reserve Bank.

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Fair value of other security investments which represent stocks that do not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount classified as loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Fair value portion of other liabilities.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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