INVESTMENT AND MORTGAGE-BACKED SECURITIES, Reconciliation of Pre-Tax OTTI Charges Recognized (Details) - Pooled Bank Trust Preferred Securities ("TRUPS") [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
OTTI Credit and Non-Credit Losses Recognized in Earnings and AOCI [Roll Forward]
Cumulative pre-tax balance at the beginning of the period	$ 9,261	$ 9,356	$ 9,295	$ 9,514
Accretion (Amortization) of previously recognized OTTI	(34)	9	(68)	(149)
Cumulative pre-tax balance at end of the period	9,227	9,365	9,227	9,365
Credit Related OTTI [Member]
OTTI Credit and Non-Credit Losses Recognized in Earnings and AOCI [Roll Forward]
Cumulative pre-tax balance at the beginning of the period	8,691	8,795	8,717	8,945
Accretion (Amortization) of previously recognized OTTI	(26)	(26)	(52)	(176)
Cumulative pre-tax balance at end of the period	8,665	8,769	8,665	8,769
Non-Credit Related OTTI [Member]
OTTI Credit and Non-Credit Losses Recognized in Earnings and AOCI [Roll Forward]
Cumulative pre-tax balance at the beginning of the period	570	561	578	569
Accretion (Amortization) of previously recognized OTTI	(8)	35	(16)	27
Cumulative pre-tax balance at end of the period	$ 562	$ 596	$ 562	$ 596