Pension Plan - Components Of Net Periodic Benefit Costs (Details) (Supplemental Employee Retirement Plans, Defined Benefit [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Components of net periodic benefit cost:
Interest cost	$ 526
Amortization of actuarial loss	128
Subtotal	654
Settlement loss, net	2,162
Net periodic benefit cost	$ 2,816
Weighted average assumption:
Discount rate	4.50%