5.625% Senior Notes, Due 2025 Face Value

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5% Senior Notes, Due 2024

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6.125% Senior Notes, Due 2022 Face Value

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Carrying value as of the balance sheet date of 6.50% Notes due 2021 with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Carrying value as of the balance sheet date of 6.625% Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Represents the amount of dividend payments excluded from the resticted dividend calculation covenant.

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Debt Instrument, Face Amount, Individual Note

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Debt Instrument, Maximum Early Redemption, Percentage of Principal

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Debt Instrument, Repurchase Premium

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Percentage of Notes Tendered

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Price per Note Tendered

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Proceeds from Debt, Net of Paid and Accrued Issuance Costs

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Fair value amount of debt instrument that was repurchased.

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Face (par) amount of the original debt instrument that was repurchased.

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-Term Debt Senior Notes (Details) - USD ($)	3 Months Ended		6 Months Ended
Long-Term Debt Senior Notes (Details) - USD ($)	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 22, 2015	Jun. 05, 2015	May. 21, 2015	May. 20, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Senior Notes	$ 2,350,000,000		$ 2,350,000,000						$ 2,200,000,000
Loss on extinguishment of debt	16,578,000	$ 0	16,578,000	$ 0
Senior Notes [Member]
Debt Instrument [Line Items]
6.625% Senior Notes, Due 2019 Face Value	0		0						350,000,000
6.50% Senior Notes, Due 2021 Face Value	350,000,000		350,000,000						350,000,000
6.125% Senior Notes, Due 2022 Face Value	600,000,000		600,000,000						600,000,000
6.50% Senior Notes, Due 2023 Face Value	400,000,000		400,000,000						400,000,000
5% Senior Notes, Due 2024 Face Value	500,000,000		500,000,000						500,000,000
5.625% Senior Notes, Due 2025 Face Value	500,000,000		500,000,000						0
Senior Notes	$ 2,350,000,000		2,350,000,000						$ 2,200,000,000
Debt Instrument, Covenant Compliance, Dividends Excluded From Computation			$ 6,500,000
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.625%		5.625%
Proceeds from Debt, Net of Paid and Accrued Issuance Costs			$ 491,100,000
Debt Instrument, Face Amount							$ 500,000,000
Debt Issuance Cost			$ 8,900,000
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member] \| Debt Instrument, Redemption, Period One [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage			105.625%
Debt Instrument, Maximum Early Redemption, Percentage of Principal			35.00%
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member] \| Debt Instrument, Redemption, Period Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage			100.00%
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member] \| Debt Instrument, Redemption, Period Three [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage			102.813%
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member] \| Debt Instrument, Redemption, Period Four [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage			101.875%
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member] \| Debt Instrument, Redemption, Period Five [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage			100.938%
Senior Notes [Member] \| 5.625% Senior Notes Due 2025 [Member] \| Debt Instrument, Redemption, Period Six [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage			100.00%
Senior Notes [Member] \| 6.625% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.625%		6.625%
Price per Note Tendered						$ 1,006.88		$ 1,036.88
Debt Instrument, Face Amount, Individual Note						1,000		1,000
Debt Instrument, Repurchased Face Amount						1,500,000		$ 242,900,000
Percentage of Notes Tendered								69.00%
Debt Instrument, Repurchase Amount						$ 1,600,000		$ 256,200,000
Loss on extinguishment of debt	$ 16,600,000
Debt Instrument, Repurchase Premium	12,500,000
Unamortized Debt Issuance Expense	$ 4,100,000		$ 4,100,000
Senior Notes [Member] \| 6.625% Senior Notes Due 2019 [Member] \| Early Debt Redemption, Year [Domain]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Amount					$ 111,500,000
Debt Instrument, Redemption Price, Percentage			103.313%
Senior Notes [Member] \| 6.125% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.125%		6.125%