Employee Benefit Plan (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) Officers	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Profit Sharing and 401(k) Plan for eligible employees [Member]
Employee Benefit Plan (Textual)
Defined benefit plan, annually cost	$ 326,000	$ 263,000	$ 235,000
Supplemental Executive Retirement Plan (nonqualified deferred compensation plan) [Member]
Employee Benefit Plan (Textual)
Defined benefit plan, annually cost	$ 978,000	352,000	$ 753,000
Number of executive officers | Officers	16
Accrued benefit obligation	$ 3,800,000	$ 2,800,000