Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - Supplemental Executive Retirement Plan - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 330	$ 291	$ 990	$ 873
Interest cost	96	74	288	221
Net periodic benefit cost	$ 426	$ 365	$ 1,278	$ 1,094