Schedule II Valuation and Qualifying Accounts (Details) (Valuation Allowance of Deferred Tax Assets [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 126,020	$ 108,004	$ 94,853
Additions	9,395	18,016	13,151
Deductions
Balance at End of Year	$ 135,415	$ 126,020	$ 108,004