FAIR VALUE MEASUREMENTS- Assets and Liabilities on Recurring and Nonrecurring Basis and Level 3 Valuation Measurements (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Investment securities available for sale	$ 672,421us-gaap_AvailableForSaleSecurities	$ 404,388us-gaap_AvailableForSaleSecurities
Derivative assets	2,368us-gaap_DerivativeAssets	4,717us-gaap_DerivativeAssets
Derivative liabilities	2,497us-gaap_DerivativeLiabilities
Foreclosed assets	12,891us-gaap_ForeclosedAssets	10,518us-gaap_ForeclosedAssets
Level 1
Investment securities available for sale	66,028	67,176
SBA loans held for investment	0	0
Derivative assets	0	0
Derivative liabilities	0
Level 2
Investment securities available for sale	595,103	329,629
SBA loans held for investment	40,404	0
Derivative assets	2,027	4,363
Derivative liabilities	2,497
Level 3
Investment securities available for sale	11,290	7,583
SBA loans held for investment	0	500
Derivative assets	342	354
Derivative liabilities	0
Recurring \| Level 1
Derivative assets	0	0
Derivative liabilities	0
Recurring \| Level 1 \| GSE obligations
Investment securities available for sale	0	0
Recurring \| Level 1 \| SBA-guaranteed securities
Investment securities available for sale	60,120	65,880
SBA-guaranteed loans held for sale	0
SBA loans held for investment	0
Recurring \| Level 1 \| Mortgage-backed securities issued by GSE
Investment securities available for sale	0	0
Recurring \| Level 1 \| Corporate bonds
Investment securities available for sale	2,545	0
Recurring \| Level 1 \| Non-agency RMBS
Investment securities available for sale	0
Recurring \| Level 1 \| Non-agency CMBS
Investment securities available for sale	0	0
Recurring \| Level 1 \| Municipal bonds
Investment securities available for sale	0	0
Recurring \| Level 1 \| Other debt securities
Investment securities available for sale	498	253
Recurring \| Level 1 \| Marketable equity securities
Investment securities available for sale	2,865	1,043
Recurring \| Level 2
Derivative assets	2,027	4,363
Recurring \| Level 2 \| GSE obligations
Investment securities available for sale	14,944	14,673
Recurring \| Level 2 \| SBA-guaranteed securities
Investment securities available for sale	0	0
SBA-guaranteed loans held for sale	8,365
SBA loans held for investment	8,906
Recurring \| Level 2 \| Mortgage-backed securities issued by GSE
Investment securities available for sale	425,283	205,260
Recurring \| Level 2 \| Corporate bonds
Investment securities available for sale	106,077	103,157
Recurring \| Level 2 \| Non-agency RMBS
Investment securities available for sale	4,963
Recurring \| Level 2 \| Non-agency CMBS
Investment securities available for sale	3,578	5,938
Recurring \| Level 2 \| Municipal bonds
Investment securities available for sale	40,258	601
Recurring \| Level 2 \| Other debt securities
Investment securities available for sale	0	0
Recurring \| Level 2 \| Marketable equity securities
Investment securities available for sale	0	0
Recurring \| Level 3
Derivative assets	342	354
Recurring \| Level 3 \| Available-for-sale Securities \| Pricing model
Investment securities available for sale	11,290	7,583
Valuation Technique	Pricing model
Unobservable Input	Illiquidity or credit factor in discount rates
Recurring \| Level 3 \| Available-for-sale Securities \| Pricing model \| Minimum
Illiquidity of credit (as a percentage)	1.00%
Recurring \| Level 3 \| Available-for-sale Securities \| Pricing model \| Maximum
Illiquidity of credit (as a percentage)	2.00%
Recurring \| Level 3 \| Interest rate lock commitments \| Pricing model
Interest rate derivative assets, at fair value	342	354
Valuation Technique	Pricing model
Unobservable Input	Pull through rates
Recurring \| Level 3 \| Interest rate lock commitments \| Pricing model \| Minimum
Pull through rates (as a percentage)	80.00%
Recurring \| Level 3 \| Interest rate lock commitments \| Pricing model \| Maximum
Pull through rates (as a percentage)	95.00%
Recurring \| Level 3 \| GSE obligations
Investment securities available for sale	0	0
Recurring \| Level 3 \| SBA-guaranteed securities
Investment securities available for sale	0	0
SBA-guaranteed loans held for sale	0
SBA loans held for investment	0
Recurring \| Level 3 \| Mortgage-backed securities issued by GSE
Investment securities available for sale	0	0
Recurring \| Level 3 \| Corporate bonds
Investment securities available for sale	11,290	7,583
Recurring \| Level 3 \| Non-agency RMBS
Investment securities available for sale	0
Recurring \| Level 3 \| Non-agency CMBS
Investment securities available for sale	0	0
Recurring \| Level 3 \| Municipal bonds
Investment securities available for sale	0	0
Recurring \| Level 3 \| Other debt securities
Investment securities available for sale	0	0
Recurring \| Level 3 \| Marketable equity securities
Investment securities available for sale	0	0
Nonrecurring \| Level 1 \| Mortgage servicing rights
Mortgage Servicing Rights		0
Nonrecurring \| Level 1 \| Impaired loans
Impaired loans	0	0
Nonrecurring \| Level 1 \| Foreclosed assets
Foreclosed assets	0	0
Nonrecurring \| Level 2 \| Mortgage servicing rights
Mortgage Servicing Rights		0
Nonrecurring \| Level 2 \| Impaired loans
Impaired loans	0	0
Nonrecurring \| Level 2 \| Foreclosed assets
Foreclosed assets	0	0
Nonrecurring \| Level 3 \| Mortgage servicing rights
Mortgage Servicing Rights		4,127
Nonrecurring \| Level 3 \| Impaired loans
Impaired loans	9,595	8,264
Nonrecurring \| Level 3 \| Impaired loans \| Discounted appraisals
Valuation Technique	Discounted appraisals
Unobservable Input	Collateral discounts
Nonrecurring \| Level 3 \| Impaired loans \| Discounted appraisals \| Minimum
Collateral discounts (as a percentage)	15.00%
Nonrecurring \| Level 3 \| Impaired loans \| Discounted appraisals \| Maximum
Collateral discounts (as a percentage)	50.00%
Nonrecurring \| Level 3 \| Impaired loans \| Discounted expected cash flows
Valuation Technique	Discounted expected cash flows
Unobservable Input	Expected loss rates
Nonrecurring \| Level 3 \| Impaired loans \| Discounted expected cash flows \| Minimum
Expected loss rates (as a percentage)	0.00%
Discount rates (as a percent)	2.00%
Nonrecurring \| Level 3 \| Impaired loans \| Discounted expected cash flows \| Maximum
Expected loss rates (as a percentage)	75.00%
Discount rates (as a percent)	8.00%
Nonrecurring \| Level 3 \| Impaired loans \| Discount rates
Unobservable Input	Discount rates
Nonrecurring \| Level 3 \| Foreclosed assets
Foreclosed assets	12,891
Nonrecurring \| Level 3 \| Foreclosed assets \| Discounted appraisals
Foreclosed assets	12,891	10,823
Valuation Technique	Discounted appraisals
Unobservable Input	Collateral discounts
Nonrecurring \| Level 3 \| Foreclosed assets \| Discounted appraisals \| Minimum
Collateral discounts (as a percentage)	15.00%
Nonrecurring \| Level 3 \| Foreclosed assets \| Discounted appraisals \| Maximum
Collateral discounts (as a percentage)	50.00%
Estimate of Fair Value Measurement
Investment securities available for sale	672,421	404,388
SBA loans held for investment	40,404	500
Derivative assets	2,368	4,717
Derivative liabilities	2,497
Estimate of Fair Value Measurement \| Recurring
Derivative assets	2,368	4,717
Estimate of Fair Value Measurement \| Recurring \| GSE obligations
Investment securities available for sale	14,944	14,673
Estimate of Fair Value Measurement \| Recurring \| SBA-guaranteed securities
Investment securities available for sale	60,120	65,880
SBA-guaranteed loans held for sale	8,365
SBA loans held for investment	8,906
Estimate of Fair Value Measurement \| Recurring \| Mortgage-backed securities issued by GSE
Investment securities available for sale	425,283	205,260
Estimate of Fair Value Measurement \| Recurring \| Corporate bonds
Investment securities available for sale	119,912	110,740
Estimate of Fair Value Measurement \| Recurring \| Non-agency RMBS
Investment securities available for sale	4,963
Estimate of Fair Value Measurement \| Recurring \| Non-agency CMBS
Investment securities available for sale	3,578	5,938
Estimate of Fair Value Measurement \| Recurring \| Municipal bonds
Investment securities available for sale	40,258	601
Estimate of Fair Value Measurement \| Recurring \| Other debt securities
Investment securities available for sale	498	253
Estimate of Fair Value Measurement \| Recurring \| Marketable equity securities
Investment securities available for sale	2,865	1,043
Estimate of Fair Value Measurement \| Nonrecurring \| Mortgage servicing rights
Mortgage Servicing Rights		4,127
Estimate of Fair Value Measurement \| Nonrecurring \| Impaired loans
Impaired loans	9,595	8,264
Estimate of Fair Value Measurement \| Nonrecurring \| Foreclosed assets
Foreclosed assets	12,891	10,823
Interest rate swaps \| Recurring \| Level 2
Derivative liabilities	2,497
Interest rate swaps \| Estimate of Fair Value Measurement \| Recurring
Derivative liabilities	$ 2,497

This represents discount rate used to revalue items held as collateral for outstanding loans.

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Fair Value, Expected Loss Rates

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Fair Value Inputs, Illiquidity in Discount Rate

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Represents impaired loans at a fair value.

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Mortgage Servicing Rights

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In the mortgage industry the pull-through rate is a percentage that measures the dollar volume of loans that a seller delivers versus the dollar volume of loans committed for delivery.

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Unobservable inputs reflect the reporting entity's own assumptions about market participant assumptions used in pricing an asset or liability.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Fair value of investments in debt securities classified as held-to-maturity.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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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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