LOANS AND ALLOWANCE FOR LOAN LOSSES (Narrative) (Details)		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2016 USD ($) property loan	Jun. 30, 2015 USD ($) loan	Jun. 30, 2016 USD ($) property loan	Jun. 30, 2015 USD ($) loan	Dec. 31, 2015 USD ($) property	Mar. 31, 2016 USD ($)	Oct. 16, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for Loan Losses Period Increase (Decrease)		$ 2,600,000		$ 3,000,000
Loans and Leases Receivable, Net Amount, Commercial		$ 23,713,000		$ 23,713,000		$ 18,322,000
Loans and Leases Period Increase (Decrease)					$ 778,300,000
Number of Loans		2		2
Financing Receivable, Allowance for Credit Losses		$ 23,717,000	$ 21,194,000	$ 23,717,000	$ 21,194,000	21,166,000	$ 21,339,000		$ 21,265,000	$ 21,116,000
Financing Receivable, Modifications, Number of Contracts			0	0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | loan		0	0	0	0
Interest lost on nonaccrual loans		$ 240,000	$ 129,000	$ 424,000	$ 272,000
Loans and Leases Receivable, Impaired, Commitment to Lend		0		0		0
Proceeds from the sale of mortgage loans				97,375,000	12,833,000
Gain on sale of mortgage loans				2,166,000	292,000
Loans held for sale		22,928,000		22,928,000		10,958,000
Other real estate owned		855,000		855,000		1,304,000
FHLB advances, general debt obligations, pledged collateral		1,100,000,000		1,100,000,000		1,100,000,000
Financing Receivable, Allowance for Credit Losses, Write-downs		(626,000)	(474,000)	(1,427,000)	(898,000)	(2,616,000)
Recoveries		150,000	152,000	254,000	285,000	728,000
Provision (credit)(1)	[1]	2,854,000	251,000	3,724,000	691,000	1,938,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		2,015,000	1,267,000	2,015,000	1,267,000	1,369,000
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		21,702,000	19,927,000	21,702,000	19,927,000	19,797,000
Financing Receivable, Individually Evaluated for Impairment		11,237,000	10,539,000	11,237,000	10,539,000	15,235,000
Financing Receivable, Collectively Evaluated for Impairment		2,574,063,000	1,796,468,000	2,574,063,000	1,796,468,000	2,474,971,000
Loans		$ 2,585,300,000	1,807,007,000	2,585,300,000	1,807,007,000	2,490,206,000
Number of Portfolio Concentration Industries		0
Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans restructured due to credit difficulties that are now performing		$ 4,500,000		4,500,000		4,800,000
Financing receivables impaired TDR non-performing		147,000		147,000		446,000
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount, Commercial		4,697,000		4,697,000		7,253,000
Financing Receivable, Allowance for Credit Losses		4,431,000	4,689,000	4,431,000	4,689,000	4,545,000	4,516,000		4,835,000	4,899,000
Mortgage Loans in Process of Foreclosure, Amount		1,700,000		1,700,000		2,900,000
Financing Receivable, Allowance for Credit Losses, Write-downs		(19,000)	(179,000)	(229,000)	(292,000)	(801,000)
Recoveries		31,000	17,000	71,000	20,000	55,000
Provision (credit)(1)		(97,000)	16,000	44,000	62,000	392,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		497,000	724,000	497,000	724,000	544,000
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		3,934,000	3,965,000	3,934,000	3,965,000	4,001,000
Financing Receivable, Individually Evaluated for Impairment		4,926,000	5,562,000	4,926,000	5,562,000	6,026,000
Financing Receivable, Collectively Evaluated for Impairment		795,630,000	581,682,000	795,630,000	581,682,000	814,591,000
Loans		800,556,000	587,244,000	800,556,000	587,244,000	820,617,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross, Commercial		11,700,000		11,700,000
Loans and Leases Receivable, Net Amount, Commercial		$ 13,752,000		$ 13,752,000		4,529,000
Number of Loans | loan		1		1
Financing Receivable, Allowance for Credit Losses		$ 11,559,000	8,160,000	$ 11,559,000	8,160,000	10,432,000	10,380,000		8,234,000	7,951,000
Financing Receivable, Allowance for Credit Losses, Write-downs		(19,000)	(48,000)	(241,000)	(103,000)	(481,000)
Recoveries		34,000	54,000	43,000	64,000	74,000
Provision (credit)(1)		1,164,000	(80,000)	1,325,000	248,000	2,888,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		29,000	240,000	29,000	240,000	644,000
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		11,530,000	7,920,000	11,530,000	7,920,000	9,788,000
Financing Receivable, Individually Evaluated for Impairment		2,340,000	3,034,000	2,340,000	3,034,000	4,610,000
Financing Receivable, Collectively Evaluated for Impairment		1,015,437,000	657,101,000	1,015,437,000	657,101,000	923,341,000
Loans		1,017,777,000	660,135,000	1,017,777,000	660,135,000	927,951,000
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for Loan Losses Period Increase (Decrease)		2,300,000
Loans and Leases Receivable, Net Amount, Commercial		$ 3,539,000		$ 3,539,000		4,489,000
Number of Loans | loan		1		1
Financing Receivable, Allowance for Credit Losses		$ 4,558,000	3,315,000	$ 4,558,000	3,315,000	3,241,000	3,298,000		3,427,000	3,354,000
Financing Receivable, Allowance for Credit Losses, Write-downs		(203,000)	(84,000)	(429,000)	(243,000)	(655,000)
Recoveries		82,000	78,000	134,000	182,000	389,000
Provision (credit)(1)		1,381,000	(106,000)	1,612,000	22,000	153,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		1,400,000	136,000	1,400,000	136,000	92,000
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		3,158,000	3,179,000	3,158,000	3,179,000	3,149,000
Financing Receivable, Individually Evaluated for Impairment		3,461,000	800,000	3,461,000	800,000	3,937,000
Financing Receivable, Collectively Evaluated for Impairment		333,056,000	261,387,000	333,056,000	261,387,000	293,784,000
Loans		336,517,000	262,187,000	336,517,000	262,187,000	297,721,000
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount, Commercial		1,611,000		1,611,000		1,933,000
Financing Receivable, Allowance for Credit Losses		2,946,000	2,144,000	2,946,000	2,144,000	2,731,000	2,622,000		2,247,000	2,247,000
Financing Receivable, Allowance for Credit Losses, Write-downs		(57,000)	(152,000)	(185,000)	(241,000)	(525,000)
Recoveries		1,000	0	2,000	5,000	188,000
Provision (credit)(1)		380,000	49,000	398,000	133,000	821,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		89,000	89,000	89,000	89,000	89,000
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		2,857,000	2,055,000	2,857,000	2,055,000	2,642,000
Financing Receivable, Individually Evaluated for Impairment		503,000	986,000	503,000	986,000	588,000
Financing Receivable, Collectively Evaluated for Impairment		341,478,000	280,071,000	341,478,000	280,071,000	348,046,000
Loans		341,981,000	281,057,000	341,981,000	281,057,000	348,634,000
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount, Commercial		4,000		4,000		118,000
Financing Receivable, Allowance for Credit Losses		$ 193,000	268,000	$ 193,000	268,000	$ 193,000	182,000		270,000	281,000
Loans in foreclosure percentage of non-performing loans		27.00%		27.00%		32.00%
Financing Receivable, Allowance for Credit Losses, Write-downs		$ (26,000)	(11,000)	$ (41,000)	(19,000)	$ (154,000)
Recoveries		2,000	3,000	4,000	14,000	22,000
Provision (credit)(1)		35,000	6,000	37,000	(8,000)	44,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		0	78,000	0	78,000	0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		193,000	190,000	193,000	190,000	193,000
Financing Receivable, Individually Evaluated for Impairment		7,000	157,000	7,000	157,000	74,000
Financing Receivable, Collectively Evaluated for Impairment		17,811,000	16,227,000	17,811,000	16,227,000	17,879,000
Loans		17,818,000	16,384,000	17,818,000	16,384,000	17,953,000
HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net Amount, Commercial		110,000		110,000		0
Financing Receivable, Allowance for Credit Losses		30,000	0	30,000	0	24,000	341,000		0	0
Financing Receivable, Allowance for Credit Losses, Write-downs		(302,000)	0	(302,000)	0	0
Recoveries		0	0	0	0	0
Provision (credit)(1)		(9,000)	0	308,000	0	24,000
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		0	0	0	0	0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		30,000	0	30,000	0	24,000
Financing Receivable, Individually Evaluated for Impairment		0	0	0	0	0
Financing Receivable, Collectively Evaluated for Impairment		70,651,000	0	70,651,000	0	77,330,000
Loans		70,651,000	0	70,651,000	0	77,330,000
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses		0	2,618,000	0	2,618,000	0	$ 0		$ 2,252,000	$ 2,384,000
Financing Receivable, Allowance for Credit Losses, Write-downs		0	0	0	0	0
Recoveries		0	0	0	0	0
Provision (credit)(1)		0	366,000	0	234,000	(2,384,000)
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment		0	0	0	0	0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment		0	2,618,000	0	2,618,000	0
Financing Receivable, Individually Evaluated for Impairment		0	0	0	0	0
Financing Receivable, Collectively Evaluated for Impairment		0	0	0	0	0
Loans		$ 0	0	$ 0	0	$ 0
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of real estate properties | property		4		4		7
Other real estate owned		$ 775,000		$ 775,000		$ 1,000,000
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of real estate properties | property		2		2		2
Other real estate owned		$ 80,000		$ 80,000		$ 241,000
Fixed Rate Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from the sale of mortgage loans		56,300,000	7,700,000	95,200,000	12,500,000
Gain on sale of mortgage loans		1,300,000	158,000	2,200,000	288,000
Loans held for sale		22,600,000		22,600,000		10,800,000
Nonoperating Income (Expense) | Fixed Rate Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain on sale of mortgage loans		$ 147,000	$ 12,000	$ 153,000	18,000
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Months		18		18
Financing Receivable, Individually Evaluated for Impairment		$ 250,000		$ 250,000
Minimum [Member] | HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
term to maturity		7 years
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Months		24		24
Maximum [Member] | HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
term to maturity		10 years
Non-Residential Building Operators Industry Sector | Loan Concentration Risk | Total Loan Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk (percentage)				12.00%
Non-Residential Building Operators Industry Sector | Loan Concentration Risk | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk (percentage)				30.00%
HPFC Subsidiary [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of days past due				45 days
Estimate of Fair Value Measurement [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and loans held for sale		$ 10,400,000		$ 10,400,000		$ 13,100,000
SBM Financial, Inc. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Period Increase (Decrease)					$ 615,400,000
Loans and loans held for sale								$ 628,030,000
SBM Financial, Inc. [Member] | Estimate of Fair Value Measurement [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and loans held for sale								$ (11,497,000)

[1] (1) The provision (credit) for loan losses excludes any impact for the change in the reserve for unfunded commitments, which represents management's estimate of the amount required to reflect the probable inherent losses on outstanding letters of credit and unused lines of credit. The reserve for unfunded commitments is presented within accrued interest and other liabilities on the consolidated statements of condition. At June 30, 2016 and 2015, and December 31, 2015, the reserve for unfunded commitments was $22,000, $26,000 and $22,000, respectively.