INVESTMENT AND MORTGAGE-BACKED SECURITIES, Reconciliation of Pre-Tax OTTI Charges Recognized (Details) - Pooled Bank Trust Preferred Securities [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
OTTI Credit and Non-Credit Losses Recognized in Earnings and AOCI [Abstract]
Cumulative pre-tax balance at the beginning of the period	$ 9,157	$ 9,295
Amortization of previously recognized OTTI	(34)	(34)
Cumulative pre-tax balance at end of the period	9,123	9,261
Credit Related OTTI [Member]
OTTI Credit and Non-Credit Losses Recognized in Earnings and AOCI [Abstract]
Cumulative pre-tax balance at the beginning of the period	8,613	8,717
Amortization of previously recognized OTTI	(26)	(26)
Cumulative pre-tax balance at end of the period	8,587	8,691
Non-Credit Related OTTI [Member]
OTTI Credit and Non-Credit Losses Recognized in Earnings and AOCI [Abstract]
Cumulative pre-tax balance at the beginning of the period	544	578
Amortization of previously recognized OTTI	(8)	(8)
Cumulative pre-tax balance at end of the period	$ 536	$ 570