Pension Plan (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Pension Plan [Abstract]
Term of employment related defined benefit pension plan, employee's compensation			10 years
Number of consecutive highest years related employees compensation			3 years
Pension plan, defined benefit [Member]
Net periodic defined benefit pension expense [Abstract]
Service cost	$ 68	$ 77	$ 136	$ 153
Interest cost	144	154	296	307
Amortization of prior service cost	22	22	44	45
Amortization of actuarial loss	95	35	191	71
Net periodic benefit cost	$ 329	$ 288	$ 667	$ 576