Valuation and Qualifying Accounts Valuation and Qualifying Accounts (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	$ 573	$ 339	$ 983	$ 486
Valuation Allowances and Reserves, Charged to Cost and Expense	234	22	504
Valuation Allowances and Reserves, Charged to Other Accounts	0	0
Valuation Allowances and Reserves, Deductions	0	(666)	(7)
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	3,394	0	43,250	66,143
Valuation Allowances and Reserves, Charged to Cost and Expense	3,394
Valuation Allowances and Reserves, Charged to Other Accounts	0	(955)	132
Valuation Allowances and Reserves, Deductions	$ 0	$ (42,295)	$ (23,025)