Long-Term Debt (Acquisition-Related Notes) (Details) (USD $)			12 Months Ended		1 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member]	Dec. 31, 2011 Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member]	Mar. 31, 2011 STARS [Member]	Dec. 31, 2012 STARS [Member]	Dec. 31, 2012 STARS [Member] Acquisition Notes [Member] Non Interest Bearing Acquisition Note [Member] Installments
Debt Instrument [Line Items]
Payments to acquire interest in joint venture					$ 20,000,000	$ 20,000,000
Debt instrument, aggregate principal amount			10,000,000				15,000,000
Debt Instrument, Number of Installment Payments							3
Debt Instrument Amount Of Installment			5,000,000				5,000,000
Long-term debt	$ 792,426,000	$ 908,295,000	$ 8,753,000	$ 13,209,000