Regulatory Matters (Basel III Rules And Other Information) (Details)	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Regulatory minimum of leverage capital to be well capitalized	5.00%	5.00%
Leverage ratio required for term of Operating Agreement	10.00%
Minimum
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Leverage ratio required for term of Operating Agreement	8.50%
Conservation Buffer [Member] | Phased In Current Fiscal Year [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of Conservation Buffer	1.25%