GOODWILL, OTHER INTANGIBLE ASSETS AND MORTGAGE SERVICING RIGHTS (Mortgage Servicing Rights) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Servicing Asset at Amortized Value, Balance [Roll Forward]
Servicing Asset at Amortized Cost, Additions, Acquisitions		$ 0		$ 2,172		$ 0
Serviced Loans
Servicing Assets at Amortized Value [Line Items]
Loans serviced for others		2,050,000		1,860,000
Mortgage Servicing Rights
Servicing Assets at Amortized Value [Line Items]
Custodial accounts		10,300		8,700
Servicing Asset at Amortized Value, Balance [Roll Forward]
Balance, beginning of the year		13,295	[1]	9,030	[1]	8,086
Amounts capitalized		5,965		5,313		3,023
Amortization	[2]	(4,011)		(3,220)		(2,079)
Valuation adjustments in the period		0
Balance, end of the year	[1]	15,249		13,295		$ 9,030
Valuation Allowance		$ 0		$ 0

[1] no valuation allowance

[2] Amortization of mortgage servicing rights is recorded as a reduction of loan servicing income and any unamortized balance is fully written off if the loan repays in full.