Derivative Instruments and Hedging Activities (Details) - Interest Rate Derivatives Portfolio - Fair Value Hedging - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 30, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross notional amount outstanding		$ 11,918	$ 12,793
Derivative liability fair value		$ (819)	$ (1,032)
Weighted-average interest rate received		2.11%	2.07%
Weighted-average interest rate paid		6.36%	6.37%
Weighted-average maturity (in years)		2 years 2 months 15 days	2 years 11 months 11 days
Fair value of assets needed to settle derivative transactions	[1]	$ 841	$ 1,057

[1] This amount represents the fair value if credit risk related contingent features were triggered.