Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of changes in unrecognized tax benefits
Balance at the beginning of the year	$ 311	$ 786	$ 804
Gross increases for tax positions taken in the current year	233	81	55
Gross increases for tax positions taken in prior years	18	0	0
Gross decreases in tax positions due to lapse in statute of limitations	(120)	(498)	(29)
Gross decreases for tax positions taken in prior years	0	(25)	(44)
Gross decreases for tax settlements with taxing authorities	0	(33)	0
Balance at the end of the year	$ 442	$ 311	$ 786