Loans and Credit Quality - Newly Restructured Loans by Concession (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Pre-modification, number of contracts | contract	1
Pre-modification, total modification	$ 210
Post-modification, number of contracts | contract	1
Post-modification, total modification	$ 210
Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
Pre-modification, number of contracts | contract	1
Pre-modification, total modification	$ 210
Post-modification, number of contracts | contract	1
Post-modification, total modification	$ 210
Rate Modification
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	0
Post-modification, total modification	0
Rate Modification | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	0
Post-modification, total modification	0
Term Modification
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	0
Post-modification, total modification	0
Term Modification | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	0
Post-modification, total modification	0
Payment Modification
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	210
Post-modification, total modification	210
Payment Modification | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	210
Post-modification, total modification	210
Combination Modification
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	0
Post-modification, total modification	0
Combination Modification | Commercial | AQR Substandard
Financing Receivable, Modifications [Line Items]
Pre-modification, total modification	0
Post-modification, total modification	$ 0