Employee Benefit Plans (Details 5) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Recognized in Other Comprehensive Income:
Net actuarial loss (gain)	$ 13,657	$ 597
Amortization of net actuarial loss (gain)	(96)	(137)
Amortization of prior service cost (credit)	(59)	(59)
Total change in other comprehensive income	$ 13,502	$ 401

Before tax amount of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

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+ Details