Contingencies, Commitments And Guarantees (Standby Letters Of Credit Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Oct. 13, 2016
Contingencies, Commitments And Guarantees [Line Items]
Outstanding letters of credit	$ 53,612	$ 205,000
0-12 Months [Member]
Contingencies, Commitments And Guarantees [Line Items]
Outstanding letters of credit	12,019
Greater Than 12 Months [Member]
Contingencies, Commitments And Guarantees [Line Items]
Outstanding letters of credit	$ 41,593