(Income Tax Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Current income tax expense	$ 0	$ 1	$ 2	$ 2
Deferred income tax expense	599	293	1,109	407
Total income tax expense	599	294	1,111	409
Net deferred tax assets	$ 12,483		$ 12,483		$ 14,115