Income Taxes (Unrecognized Tax Benefits) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	$ 7,300	$ 600	$ 500
Additions/(reductions) based on tax positions related to the current year	2,200	6,300	0
Additions for tax positions of prior years	0	400	400
Reductions for tax positions of prior years	0	0	(300)
Balance at end of period	9,500	7,300	600
Unrecognized tax benefits that would impact effective tax rate	1,100
Unrecognized tax benefit, income tax expense			100
Unrecognized tax benefits, interest on income taxes expense / (benefits)	200	(100)	(200)
Unrecognized tax benefits, income tax penalties and interest accrued	$ 400	$ 200