Deposits and Related Interest (Narratives) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deposits [Abstract]
Weighted Average Rate Domestic Deposit	0.65%	0.62%
Puerto Rico Cash & Money Market Fund Deposits		$ 15,300
Puerto Rico Cash & Money Market Fund Deposits Weighted Average Rate		0.77%
Time Deposits, $250,000 or More	$ 359,600	$ 344,000
Public Fund Time Deposits, $250,000 or more	$ 3,500	$ 2,100
Public Fund Time Deposits Weighted Average Rate, $250,000 or more	0.28%	0.50%
Public funds deposit	$ 153,100	$ 170,700
Public Fund Collateral Investments	173,000	209,200
Accrued Interest, Time Deposits	1,900
Bank Overdrafts	2,200	575
Brokered Certificates of Deposits	471,600	508,400
Brokered Money Market Deposit	$ 46,900	$ 68,000