FAIR VALUE OF FINANCIAL INSTRUMENTS, Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Marketable equity securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds	$ 1,420
International Equity Mutual Funds	377
Fixed Income Mutual Funds	3,870
Trading securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds		$ 460
International Equity Mutual Funds		120
Fixed Income Mutual Funds		2,135
Investment securities available-for-sale [Abstract]
Agency Notes	25,145
Corporate Securities	11,135
Domestic Equity Mutual Funds		1,512
International Equity Mutual Funds		445
Fixed Income Mutual Funds		2,049
Pass-through MBS issued by GSEs	354,613	72,629
Agency CMOs	111,992	278,755
Loans held for sale	1,097
Derivative - interest rate product	4,669	4,041
Financial Liabilities [Abstract]
Derivative - interest rate product	2,097
Level 1 Inputs [Member]
Marketable equity securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds	1,420
International Equity Mutual Funds	377
Fixed Income Mutual Funds	3,870
Trading securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds		460
International Equity Mutual Funds		120
Fixed Income Mutual Funds		2,135
Investment securities available-for-sale [Abstract]
Agency Notes	0
Corporate Securities	0
Domestic Equity Mutual Funds		1,512
International Equity Mutual Funds		445
Fixed Income Mutual Funds		2,049
Pass-through MBS issued by GSEs	0	0
Agency CMOs	0	0
Loans held for sale	0
Derivative - interest rate product	0	0
Financial Liabilities [Abstract]
Derivative - interest rate product	0
Level 2 Inputs [Member]
Marketable equity securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds	0
International Equity Mutual Funds	0
Fixed Income Mutual Funds	0
Trading securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds		0
International Equity Mutual Funds		0
Fixed Income Mutual Funds		0
Investment securities available-for-sale [Abstract]
Agency Notes	25,145
Corporate Securities	11,135
Domestic Equity Mutual Funds		0
International Equity Mutual Funds		0
Fixed Income Mutual Funds		0
Pass-through MBS issued by GSEs	354,613	72,629
Agency CMOs	111,992	278,755
Loans held for sale	1,097
Derivative - interest rate product	4,669	4,041
Financial Liabilities [Abstract]
Derivative - interest rate product	2,097
Level 3 Inputs [Member]
Marketable equity securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds	0
International Equity Mutual Funds	0
Fixed Income Mutual Funds	0
Trading securities (Registered Mutual Funds) [Abstract]
Domestic Equity Mutual Funds		0
International Equity Mutual Funds		0
Fixed Income Mutual Funds		0
Investment securities available-for-sale [Abstract]
Agency Notes	0
Corporate Securities	0
Domestic Equity Mutual Funds		0
International Equity Mutual Funds		0
Fixed Income Mutual Funds		0
Pass-through MBS issued by GSEs	0	0
Agency CMOs	0	0
Loans held for sale	0
Derivative - interest rate product	0	$ 0
Financial Liabilities [Abstract]
Derivative - interest rate product	$ 0

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Fair value of financial and nonfinancial obligations.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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