Employee Benefit Plans (Additional Information) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
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%	2.00%
Expenses under the 401(K)/Profit Sharing plan	$ 1,200	$ 1,100	$ 1,000
Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum guaranteed benefit term	15 years
Accumulated benefit obligation	7,900	7,200
Expected amortization of net actuarial loss	224
Expected amortization of prior service cost	19
Expected contributions in 2013	531
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	47
Expected contributions in 2013	$ 154