INVESTMENT AND MORTGAGE-BACKED SECURITIES, Major Categories of Securities Owned (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
		Sep. 30, 2017 USD ($) Security	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) Security	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Investment Securities Held-to-Maturity [Abstract]
Amortized Cost		$ 0		$ 0		$ 5,378
Fair Value						7,296
Investment Securities Available-for-sale [Abstract]
Amortized Cost		31,329		31,329		7,618	[1]
Gross Unrealized Gains		275		275		74
Gross Unrealized Losses		(189)		(189)		(239)
Fair Value		31,415		31,415		7,453
Total Investment Securities [Abstract]
Amortized Cost	[1]					12,996
Gross Unrealized Gains						2,295
Gross Unrealized Losses						(542)
Fair Value						14,749
Sale of TRUP CDO securities [Abstract]
Gross proceeds from sale of securities				9,167	$ 0
Investment securities available-for-sale (Registered Mutual Funds) [Abstract]
Proceeds				240	0
Trading securities [Abstract]
Proceeds				4,629	3,648
Pooled Bank Trust Preferred Securities [Member]
Investment Securities Held-to-Maturity [Abstract]
Amortized Cost	[1]					5,378
Gross Unrealized Gains						2,221
Gross Unrealized Losses						(303)
Fair Value						7,296
Sale of TRUP CDO securities [Abstract]
Unamortized portion of the unrealized loss amount recognized		$ 705		$ 705		755
Number of TRUP CDO securities deemed OTTI | Security		5		5
Amortized cost TRUP CDO portfolio		$ 5,331		$ 5,331
OTTI charges		8,553
Gross proceeds from sale of securities		9,167		9,167
Gross gains recognized from sale of securites		3,048		3,048
Gross losses recognized on sale of securites		411		411
Registered Mutual Funds [Member]
Investment Securities Available-for-sale [Abstract]
Amortized Cost		3,824		3,824		4,011	[1]
Gross Unrealized Gains		262		262		62
Gross Unrealized Losses		(52)		(52)		(178)
Fair Value		4,034		4,034		3,895
Investment securities available-for-sale (Registered Mutual Funds) [Abstract]
Proceeds		137	$ 0	240	0
Pass-through MBS Issued by Government Sponsored Entities ("GSEs") [Member]
Investment Securities Available-for-sale [Abstract]
Amortized Cost		16,739		16,739		360	[1]
Gross Unrealized Gains		12		12		12
Gross Unrealized Losses		(67)		(67)		0
Fair Value		16,684		$ 16,684		372
Investment and Mortgage-Backed Securities [Abstract]
Securities weighted average term to maturity				19 years 8 months 12 days
Weighted average estimated duration				3 years 2 months 12 days
Sale of TRUP CDO securities [Abstract]
Proceeds from sales of mortgage backed securities available-for-sale		0	0	$ 0	0
Agency Collateralized Mortgage Obligation ("CMO") [Member]
Investment Securities Available-for-sale [Abstract]
Amortized Cost		10,766		10,766		3,247	[1]
Gross Unrealized Gains		1		1		0
Gross Unrealized Losses		(70)		(70)		(61)
Fair Value		10,697		$ 10,697		$ 3,186
Investment and Mortgage-Backed Securities [Abstract]
Securities weighted average term to maturity				16 years 8 months 12 days
Weighted average estimated duration				2 years 3 months 18 days
Sale of TRUP CDO securities [Abstract]
Proceeds from sales of mortgage backed securities available-for-sale		0	0	$ 0	0
Trading Securities [Member]
Trading securities [Abstract]
Proceeds		85	0	4,629	3,648
Gross gains		3	0	66	3
Gross losses		$ 0	$ 0	$ 25	$ 45

[1] Amount represents the purchase amortized / historical cost less any OTTI charges (credit or non-credit related) previously recognized. For the TRUP CDOs, amount is also net of the $755 unamortized portion of the unrealized loss that was recognized in accumulated other comprehensive loss on September 1, 2008 (the day on which these securities were transferred from available-for-sale to held-to-maturity).