Loans and Credit Quality - Restructured Loans (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	$ 10,375
Existing Troubled Debt Restructurings	15,030
Total	25,405	$ 16,200
Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	10,375
Accrual Status
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	210
Existing Troubled Debt Restructurings	5,468
Total	5,678
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	10,165
Existing Troubled Debt Restructurings	9,562
Total	19,727
Nonaccrual Status | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
New Troubled Debt Restructurings	$ 10,165