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 Issued.

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Equity Units, ownership interest percentage In remarketable subordinated notes

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The number of shares of our common stock issued at settlement for each purchase contract of Equity Units.

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Debt instrument, repurchased face amount.

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No definition available.

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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

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.

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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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No definition available.

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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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.

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No definition available.

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- Definition

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

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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.

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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.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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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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Number of new stock issued during the period.

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Debt (Narrative) (Details) - USD ($)		3 Months Ended		6 Months Ended
Debt (Narrative) (Details) - USD ($)	May 01, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 02, 2018	May 12, 2015
Debt Instrument [Line Items]
Repayments of Long-term Debt				$ 73,000,000	$ 663,000,000
Gain (Loss) on extinguishment of debt		$ 0	$ 1,000,000	1,000,000	(18,000,000)
Short-term borrowings		1,010,000,000		1,010,000,000			$ 1,145,000,000
Commercial paper		900,000,000		900,000,000			697,000,000
Equity Unit Purchase Agreements [Member]
Debt Instrument [Line Items]
Equity Units Issued									25,000,000
Equity Units, stated value per unit (whole dollars)									$ 50
Equity Units, ownership interest percentage in remarketable subordinated notes									5.00%
Debt instrument, face amount									$ 1,250,000,000
Equity Units Stock Purchase Contracts Settlement Rate	0.2412
Issuance of common stock under Equity Units stock purchase contracts, shares	6,000,000.0
Convertible Debt [Member]
Debt Instrument [Line Items]
Repurchased Face Amount				20,000,000
Repayments of Long-term Debt				73,000,000
Gain (Loss) on extinguishment of debt				1,000,000
Lines of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		600,000,000		600,000,000
Short-term borrowings		300,000,000		300,000,000			500,000,000
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, advances, short-term		$ 710,000,000		$ 710,000,000			$ 645,000,000
Debt instrument interest rate		2.437%		2.437%			2.458%
Surplus Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 25,000,000		$ 25,000,000			$ 25,000,000
Remarketable Subordinated Notes [Member]
Debt Instrument [Line Items]
Remarketable subordinated notes tendered, cash payment					4,000,000
Gain (Loss) on extinguishment of debt					$ (18,000,000)
Remarketable Subordinated Notes [Member] \| Four Point One Zero One Percent Due Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Debt instrument, face amount								$ 1,250,000,000
Remarketable Subordinated Notes [Member] \| Four Point Five Five Zero Percent Due Two Thousand Forty Eight [Member]
Debt Instrument [Line Items]
Debt instrument, face amount								$ 850,000,000
Remarketable Subordinated Notes [Member] \| One Point Nine Zero Zero Percent Due Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Debt instrument, face amount									$ 1,000
Debt Instrument, Interest Rate, Stated Percentage									1.90%
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		17,182,000,000		17,182,000,000			17,153,000,000
Commercial Paper Program
Debt Instrument [Line Items]
Commercial paper authorized		2,500,000,000		2,500,000,000
Commercial paper		900,000,000		900,000,000			$ 697,000,000
364-Day Facility [Member] \| Senior Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		1,000,000,000		1,000,000,000
5-Year Facility [Member] \| Senior Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 2,500,000,000		$ 2,500,000,000		$ 3,500,000,000