Employee Benefit Plans (Additional Information) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
401(k)/Profit Sharing Plan
Contribution match, as a percentage of annual pay	4.00%
Contribution matches, percentage of pre-tax compensation	3.00%	3.00%	3.00%
Expenses under the 401(K)/Profit Sharing plan	$ 1,400,000	$ 1,400,000	$ 1,200,000
Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum guaranteed benefit term	15 years
Accumulated benefit obligation	8,500,000	8,000,000
Expected amortization of net actuarial loss	218,000
Expected amortization of prior service cost	19,000
Supplemental Executive Retirement Plan [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of income replaced	65.00%
Supplemental Executive Retirement Plan [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of income replaced	75.00%
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected amortization of net actuarial loss	24,000
Expected amortization of prior service cost	22,000
Defined Benefit Plan, Effect of Plan Amendment on Accumulated Benefit Obligation	$ 308,000