Derivative and Hedging Activities Derivative and Hedging Activities - Offsetting of Derivative Assets and Liabiltiies (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 54
Derivative Asset, Fair Value, Gross Liability	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	54
Derivative, Collateral, Obligation to Return Securities	(9)
Derivative, Collateral, Obligation to Return Cash	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	45
Derivative Liability, Fair Value, Gross Liability	40
Derivative Liability, Fair Value, Gross Asset	0
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	40
Derivative Liability, Securities Sold under Agreements to Resell, Securities Loaned, Collateral, Right to Reclaim Securities	(9)
Derivative, Collateral, Right to Reclaim Cash	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 31