Loans (Narrative) (Details)	9 Months Ended
	Sep. 30, 2017 USD ($) contract	Dec. 31, 2016 USD ($)
Financing Receivable, Impaired [Line Items]
Risk rate loans, aggregate balance threshold	$ 2,500,000
Risk rate loans, loan balance threshold	500,000
Troubled debt restructurings included in impaired loans	29,100,000	$ 28,600,000
Current Troubled debt restructurings included in impaired loans	$ 28,300,000	$ 28,100,000
Number of days past due to be considered in default	30 days
Non-Jumbo [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | contract	4
Land and Land Improvements [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | contract	1