Accumulated Other Comprehensive Income (Reclassifications out of other comprehensive income) (Details) - Reclassification out of Accumulated Other Comprehensive Income [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest Rate Contract	$ 1,875	$ 488	$ 3,642
Tax effect from increase in capital gains tax rate, Cash flow hedges	0	0	300
Gain On Sale Of Investments	0	6,896	12,207
Residual tax effect from OIB's change in applicable tax rate AFS	5	104	32
Tax effect from increase in capital gains tax rate AFS	(235)	(284)	(293)
Total	$ 1,645	$ 7,204	$ 15,888

Accumulated Other Comprehensive Income (Reclassifications out of other comprehensive income) (Details) - Reclassification out of Accumulated Other Comprehensive Income [Member] - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2018

Dec. 31, 2017

Dec. 31, 2016

Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]

Interest Rate Contract

$ 1,875

$ 488

$ 3,642

Tax effect from increase in capital gains tax rate, Cash flow hedges

300

Gain On Sale Of Investments