FEDERAL HOME LOAN BANK ADVANCES - LOANS PLEDGED (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
First lien, single family residential real estate
Real estate loans pledged to collateralize advances and letters of credit with the FHLB
Real estate loans pledged to collateralize advances and letters of credit with FHLB	$ 1,213,275	$ 1,346,663
Home equity lines of credit
Real estate loans pledged to collateralize advances and letters of credit with the FHLB
Real estate loans pledged to collateralize advances and letters of credit with FHLB	301,159	272,863
Multi-family commercial real estate
Real estate loans pledged to collateralize advances and letters of credit with the FHLB
Real estate loans pledged to collateralize advances and letters of credit with FHLB	$ 9,692	$ 10,227