Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Changes in our liability for unrecognized gross tax benefits
Balance at beginnng of year	$ 2,522	$ 2,274	$ 3,821
Tax position of current year	145	160	289
Tax position of prior years	2,988	763	259
Statute expirations	(713)	(595)	(1,244)
Settlements	(404)	0	0
Tax positions of prior years	(409)	(80)	(851)
Balance at end of year	$ 4,129	$ 2,522	$ 2,274