Income Taxes (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Change in unrecognized tax benefits
Balance, beginning of the year	$ 4,279,000	$ 4,164,000
Additions for tax positions of current year	194,000	443,000
Reductions for tax positions of prior years		(273,000)
Settlements		(55,000)
Balance, end of the year	4,473,000	4,279,000	4,164,000
Portion of Unrecognized tax benefits, if recognized, would impact effective tax rate	2,900,000	2,800,000
Interest and penalties expense (benefit) relating to uncertain tax positions	200,000	400,000	(400,000)
Accrued interest and penalties relating to uncertain tax positions	$ 3,400,000	$ 3,200,000