Loans Loans - Restructured Loans Past Due in Excess of 90 Days on Financing Receivables (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($) Item	Mar. 31, 2017 USD ($) Item
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured During The Last Year In Excess of 90 Days Past Due | Item	0	1
Dollar amount of previously restructured loans past due	$ 0	$ 747
Restructured loans on non-accrual status at period end	14,229	11,212
Charge-offs of restructured loans recognized in connection with restructuring	0	0
Charge-offs of restructured loans recognized on previously restructured loans	1,650	2,000
Non Accrual Loans [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans on non-accrual status at period end	$ 2,171	$ 11,212