INVESTMENT SECURITIES AVAILABLE FOR SALE - Classified (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Investment securities classified as available for sale
Amortized cost	$ 383,707,000		$ 383,707,000		$ 247,525,000
Gross unrealized gains	2,503,000		2,503,000		848,000
Gross unrealized losses	870,000		870,000		2,034,000
Investment securities available for sale	385,340,000		385,340,000		246,339,000
Available-for-sale Securities	385,340,000		385,340,000		246,339,000
Available-for-sale Securities, Gross Realized Gains	55,000	$ 72,000	122,000	$ 276,000
U.S. Treasury securities
Investment securities classified as available for sale
Amortized cost	25,993,000		25,993,000		75,973,000
Gross unrealized losses	57,000		57,000		72,000
Investment securities available for sale	25,936,000		25,936,000		75,901,000
Available-for-sale Securities	25,936,000		25,936,000		75,901,000
Government sponsored entity debt securities
Investment securities classified as available for sale
Amortized cost	19,770,000		19,770,000		7,653,000
Gross unrealized gains	87,000		87,000		57,000
Gross unrealized losses	14,000		14,000		22,000
Investment securities available for sale	19,843,000		19,843,000		7,688,000
Available-for-sale Securities	19,843,000		19,843,000		7,688,000
Agency mortgage-backed securities
Investment securities classified as available for sale
Amortized cost	242,021,000		242,021,000		90,629,000
Gross unrealized gains	1,119,000		1,119,000		373,000
Gross unrealized losses	590,000		590,000		932,000
Investment securities available for sale	242,550,000		242,550,000		90,070,000
Available-for-sale Securities	242,550,000		242,550,000		90,070,000
Non-agency mortgage-backed securities
Investment securities classified as available for sale
Amortized cost					1,000
Investment securities available for sale					1,000
Available-for-sale Securities					1,000
State and municipal securities
Investment securities classified as available for sale
Amortized cost	39,813,000		39,813,000		25,826,000
Gross unrealized gains	409,000		409,000		15,000
Gross unrealized losses	40,000		40,000		567,000
Investment securities available for sale	40,182,000		40,182,000		25,274,000
Available-for-sale Securities	40,182,000		40,182,000		25,274,000
Corporate securities
Investment securities classified as available for sale
Amortized cost	53,418,000		53,418,000		47,443,000
Gross unrealized gains	790,000		790,000		403,000
Gross unrealized losses	159,000		159,000		441,000
Investment securities available for sale	54,049,000		54,049,000		47,405,000
Available-for-sale Securities	54,049,000		54,049,000		$ 47,405,000
Equity securities
Investment securities classified as available for sale
Amortized cost	2,692,000		2,692,000
Gross unrealized gains	98,000		98,000
Gross unrealized losses	10,000		10,000
Investment securities available for sale	2,780,000		2,780,000
Available-for-sale Securities	$ 2,780,000		$ 2,780,000

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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