Loans and Credit Quality - Restructured Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	$ 0
Existing Troubled Debt Restructurings	13,167
Total	13,167	$ 14,800
Accrual Status
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	0
Existing Troubled Debt Restructurings	3,368
Total	3,368
Nonaccrual Status
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	0
Existing Troubled Debt Restructurings	9,799
Total	$ 9,799