Income Taxes (Details 5) (USD $)	12 Months Ended
	Dec. 31, 2012 state	Dec. 31, 2011
Change in unrecognized tax benefits
Balance at the beginning of the period	$ 4,748,000	$ 3,660,000
Additions for tax positions related to current year	435,000	1,069,000
Additions for tax positions relating to prior years	742,000	1,209,000
Reductions for tax positions relating to prior years	(59,000)	(422,000)
Reductions due to the lapse of the applicable statute of limitations	(48,000)	(586,000)
Settlements		(182,000)
Balance at the end of the period	5,818,000	4,748,000
Accrued interest and penalties related to unrecognized tax benefits	$ 500,000	$ 200,000
Number of states currently under examination for open tax years between 2007 and 2010	2