Long-Term Debt (Long-Term Debt Maturities) (Details) (USD $)	Sep. 30, 2012
Long-Term Debt Disclosure [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 0
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	695,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Four	0
Long-term Debt, Maturities, Repayments of Principal in Year Five	162,500,000
Long-term Debt, Maturities, Repayments of Principal after Year Five	1,100,000,000
Long-term Debt Maturities, Total Repayments of Principal	1,957,500,000	[1]
Debt Instrument, Unamortized Premium	$ 2,900,000

[1] Excludes unamortized premiums of $2.9 million as of September 30, 2012.