SECURITIES (Textuals) (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) security	Dec. 31, 2018 USD ($) security	Dec. 31, 2017 USD ($) security
Investments, Debt and Equity Securities [Abstract]
Trading securites, proceeds from sale	$ 0	$ 0	$ 1,258,000
Trading Securities, Realized Gain (Loss)			28,000
Trading securities, OTTI charges	$ 0	$ 0	$ 0
Trading securities, number of securities in nonaccrual status | security	0	0	0
Trading securities, unrealized holding gain		$ 3,800,000
Available-for-Sale:
Available-for-sale securities, unrealized loss position, number of securities | security	90	271
Available-for-sale securities, proceeds from sale	$ 66,300,000	$ 214,600,000	$ 522,600,000
Debt Securities, Available-for-sale, Realized Gain (Loss)	46,000
Debt Securities, Available-For-Sale, Realized Gain (Loss), Partial Calls	(12,000)
Available-for-sale securities, Realized Gain (Loss)		(839,000)	(2,100,000)
Available-for-sale securities, OTTI charges	$ 0	$ 0	$ 0
Available-for-sale Securities, Number of Securities in Nonaccrual Status | security	0	0	0
Held-to-Maturity:
Held-to-maturity Securities, unrealized loss position, number of securities | security	17	90
Held-to-maturity Securities, proceeds from sale	$ 0	$ 0	$ 0
Debt Securities, Held-to-maturity, Sold, Realized Gain (Loss), Excluding Other-than-temporary Impairment	$ (1,000)	$ 2,000,000
Held-to-maturity securities, number of securities in nonaccrual status | security	0	0	0