Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2012 Age	Dec. 31, 2011	Dec. 31, 2010
Benefit Plans (Textual) [Abstract]
Additional compensation of employer		10.00%
Description for applicability of compensation program		Distributions from the applicable trust are made upon or shortly after the executive reaches age 70, disability, death, or earlier election by the executive after age 60
Senior executive age for participate in plan		70
Senior executive age for earlier election		60
Defined contribution plan eligibility minimum service period	1 year
Defined contribution retirement plan, Maximum matching contribution percentage		5.00%
Aggregate contribution of employer		$ 643	$ 530	$ 531