Fair Value Measurements (Details Textuals) (USD $)	3 Months Ended		9 Months Ended			3 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Mar. 31, 2012 Faustina Investment Impairment [Member]
Fair Value Measurements (details) [Abstract]
Long-term Debt, Fair Value	$ 2,260,000,000		$ 2,260,000,000		$ 2,253,200,000
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount					13,800,000
Accrued dividends receivable					1,300,000
Components Of Impairment Nonoperating [Line Items]
Other Asset Impairment Charges	$ 0	$ 0	$ 17,515,000	$ 0		$ 15,100,000