Loans Held for Sale and Loan Servicing Loans sold during the period (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold	$ 135,545	$ 131,706	$ 94,892
Net gains on sale	2,898	2,871	2,097
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold	135,294	131,706	94,892
Net gains on sale	2,880	2,871	2,097
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold	251	0	0
Net gains on sale	$ 18	$ 0	$ 0