SECURITIES (Narrative) (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) security	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) security	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) security
Schedule of Investments [Line Items]
Net unrealized gains (losses) on available-for-sale securities, net of tax	$ 7,347,000		$ 7,347,000		$ (3,801,000)
Deferred tax assets, unrealized losses on available for sale securities	$ 4,000,000		4,000,000		$ 2,000,000
Payments to acquire investments			$ 108,400,000	$ 96,200,000
AFS securities in unrealized loss positions, number of positions | security	20		20		110
AFS and HTM securities in Continues Unrealized Loss Position	$ 130,000,000		$ 130,000,000		$ 546,100,000
AFS and HTM Securities Unrealized Loss Accumulated in Investments	1,500,000		1,500,000		10,200,000
Fair Value - 12 Months of More	$ 127,623,000		$ 127,623,000		$ 192,809,000
Unrealized Loss as a Percent of Fair Value	0.00%		0.00%		2.00%
Proceeds from Sale of Available-for-sale Securities	$ 84,000	$ 0	$ 84,000	0
Available-for-sale Securities, Gross Realized Gains	4,000	0	4,000	0
Investment securities sold, carrying amount		$ 0
Federal Home Loan Bank Stock	23,500,000		23,500,000		$ 20,600,000
Federal Reserve Bank Stock	5,400,000		5,400,000		908,000
Security pledged as collateral, amortized cost	549,300,000		549,300,000		577,600,000
Security pledged as collateral, fair value	555,900,000		555,900,000		570,900,000
Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
AFS and HTM Securities Unrealized Loss Accumulated in Investments	1,500,000		1,500,000		6,700,000
Fair Value - 12 Months of More	$ 129,600,000		$ 129,600,000		$ 192,800,000
AFS securities in unrealized loss positions, number of positions greater than or equal to one year | security	19		19		28
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Schedule of Investments [Line Items]
Fair Value - 12 Months of More	$ 33,618,000		$ 33,618,000		$ 45,629,000
Available-for-sale Securities
Schedule of Investments [Line Items]
Payments to acquire investments			98,700,000	56,000,000
Held-to-maturity Securities
Schedule of Investments [Line Items]
Payments to acquire investments			$ 9,700,000	$ 40,200,000