Commitments and Off-balance Sheet Items (Narrative) (Details)	12 Months Ended
	Dec. 31, 2017
Minimum
Commitments and Contingent Liabilities [Line Items]
Loans and Leases Receivable Fixed Commitment Interest Rates	2.00%
Loans and Leases Receivable Fixed Commitment Maturity	1 year
Maximum
Commitments and Contingent Liabilities [Line Items]
Loans and Leases Receivable Fixed Commitment Interest Rates	18.00%
Loans and Leases Receivable Fixed Commitment Maturity	32 years