Commercial Paper, Maximum Borrowing Capacity

No definition available.

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- Definition

Equity Unit, stated value per unit.

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Equity Units, Contract Annual Rate

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- Definition

Equity Units Issued.

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- Definition

Equity Units, ownership interest percentage In remarketable subordinated notes

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- Definition

Number of lines of credit

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- Definition

Present value of stock purchase contract liability related to Equity Units. This amount represents the offset to additional paid-in-capital.

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- Definition

Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

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

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- Definition

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

+ References

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- Definition

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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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Describe the settlement alternatives of the freestanding contract as either (i) physical settlement; (ii) net-share settlement; or, (iii) net-cash settlement. Physical settlement is when the party designated in the contract as the buyer delivers the full stated amount of cash to the seller, and the seller delivers the full stated number of shares to the buyer. Net-share settlement is when the party with a loss delivers to a party with a gain shares with a current fair value equal to the gain. Net-cash settlement is when the party with a loss delivers to the party with a gain a cash payment equal to the gain, and no shares are exchanged. Discuss also who controls the settlement alternatives and the maximum number of shares that could be required to be issued to net share settle a contract. If a contract does not have a fixed or determinable maximum number of shares that may be required to be issued, the fact that a potentially infinite number of shares could be required to be issued to settle the contract would generally be expected to be disclosed.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Expenses paid for obtaining loans which includes expenses such as application and origination fees.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt (Narrative) (Details) - USD ($) shares in Millions	3 Months Ended	9 Months Ended		12 Months Ended
Debt (Narrative) (Details) - USD ($) shares in Millions	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2015	Jun. 15, 2017	Feb. 15, 2017	Jan. 23, 2017	Dec. 31, 2016	May 12, 2015
Debt Instrument [Line Items]
Short-term borrowings		$ 1,180,000,000						$ 440,000,000
Equity Unit Purchase Agreements [Member]
Debt Instrument [Line Items]
Equity Units Issued									25.0
Outstanding principal amount		1,250,000,000
Equity Units, stated value per unit (whole dollars)		$ 50
Equity Units, ownership interest percentage in remarketable subordinated notes		5.00%
Par value, remarketable subordinated notes		$ 1,000
Forward Contract Indexed to Issuer's Equity, Settlement Alternatives		On May 1, 2018, if the applicable market value of our common stock is equal to or greater than $207.5898 per share, the settlement rate will be 0.2406 shares of our common stock. If the applicable market value of our common stock is less than $207.5898 per share but greater than $143.7160 per share, the settlement rate will be a number of shares of our common stock equal to $50 (whole dollars) divided by the applicable market value of our common stock. If the applicable market value of common stock is less than or equal to $143.7160, the settlement rate will be 0.3480 shares of our common stock. Holders of the Equity Units may elect early settlement at a minimum settlement rate of 0.2406 shares of our common stock for each purchase contract being settled.
Stock purchase contract liability, present value		$ 31,200,000
Equity Units, contract adjustment payment rate		3.35%
Senior Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 3,500,000,000
Convertible Debt [Member]
Debt Instrument [Line Items]
Outstanding principal amount		512,600,000
Bridge Loan [Member]
Debt Instrument [Line Items]
Bridge facility fees		97,500,000		$ 106,600,000
Bridge Loan							$ 19,500,000,000	22,500,000,000
Amoritization of bridge facility fees	$ 19,000,000	$ 107,900,000	$ 82,100,000
Lines of Credit [Member]
Debt Instrument [Line Items]
Number of lines of credit		2
Maximum borrowing capacity		$ 450,000,000
Short-term borrowings		450,000,000
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, advances, short-term		$ 730,000,000
Debt instrument interest rate		1.183%
Surplus Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 24,900,000						24,900,000
Remarketable Subordinated Notes [Member] \| One Point Nine Zero Zero Percent Due Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.90%
Long-term Debt		$ 1,238,400,000						1,237,600,000
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		12,135,700,000						13,061,300,000
Senior Unsecured Notes [Member] \| Five Point Eight Seven Five Percent Due Two Thousand Seventeen [Member]
Debt Instrument [Line Items]
Debt instruments, repurchased face amount					$ 528,800,000
Debt Instrument, Interest Rate, Stated Percentage					5.875%
Senior Unsecured Notes [Member] \| Two Point Three Seven Five Percent Due Two Thousand And Seventeen [Member]
Debt Instrument [Line Items]
Debt instruments, repurchased face amount						$ 400,000,000
Debt Instrument, Interest Rate, Stated Percentage						2.375%
Commercial Paper Program
Debt Instrument [Line Items]
Commercial paper authorized		2,500,000,000
Commercial paper		$ 1,315,500,000						$ 629,000,000