Loans and Credit Quality - Restructured Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	$ 210
Existing Troubled Debt Restructurings	15,997
Total	16,207	$ 16,200
Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	210
Accrual Status
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	210
Existing Troubled Debt Restructurings	6,080
Total	6,290
Accrual Status | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	210
Nonaccrual Status
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	0
Existing Troubled Debt Restructurings	9,917
Total	9,917
Nonaccrual Status | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	$ 0