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SECURITIES AVAILABLE FOR SALE, HELD TO MATURITY, AND MARKETABLE EQUITY SECURITIES - Narrative (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($) security	Jun. 30, 2019 USD ($) security	Jun. 30, 2018 USD ($)
Investment Holdings [Line Items]
Purchases of securities available for sale | $		$ 15,180	$ 165,312
Proceeds from sale of available-for-sale securities | $	$ 80,400	82,978	$ 0
Debt securities, available-for-sale, realized gain | $	5	11
Debt securities, available-for-sale, realized loss | $	$ 7	$ 7
Municipal bonds and obligations
Investment Holdings [Line Items]
Available-for-sale, securities in unrealized loss positions	2	2
Available for sale securities portfolio, number of securities		246
Available for sale securities, continuous unrealized loss position, aggregate losses		0.40%
Agency collateralized mortgage obligations
Investment Holdings [Line Items]
Available-for-sale, securities in unrealized loss positions	59	59
Available for sale securities portfolio, number of securities		253
Available for sale securities, continuous unrealized loss position, aggregate losses		0.40%
Held-to-maturity, securities in unrealized loss positions	1	1
Held-to-maturity securities portfolio, number of securities	9	9
Held to maturity securities, continuous unrealized loss position, aggregate losses		0.80%
Mortgage-backed securities
Investment Holdings [Line Items]
Available-for-sale, securities in unrealized loss positions	45	45
Available for sale securities portfolio, number of securities		97
Available for sale securities, continuous unrealized loss position, aggregate losses		1.40%
Held-to-maturity, securities in unrealized loss positions	1	1
Held-to-maturity securities portfolio, number of securities	2	2
Held to maturity securities, continuous unrealized loss position, aggregate losses		0.80%
Corporate bonds
Investment Holdings [Line Items]
Available-for-sale, securities in unrealized loss positions	11	11
Available for sale securities portfolio, number of securities		23
Available for sale securities, continuous unrealized loss position, aggregate losses		1.50%
Trust preferred securities
Investment Holdings [Line Items]
Available-for-sale, securities in unrealized loss positions	1	1
Available for sale securities portfolio, number of securities		2
Available for sale securities, continuous unrealized loss position, aggregate losses		0.10%
Other bonds and obligations
Investment Holdings [Line Items]
Available-for-sale, securities in unrealized loss positions	6	6
Available for sale securities portfolio, number of securities		10
Available for sale securities, continuous unrealized loss position, aggregate losses		0.20%
Tax advantaged economic development bonds
Investment Holdings [Line Items]
Held-to-maturity, securities in unrealized loss positions	1	1
Held-to-maturity securities portfolio, number of securities	5	5
Held to maturity securities, continuous unrealized loss position, aggregate losses		15.80%

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