Debt instrument redemption amount.

No definition available.

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- Definition

Number Of Cash Tender Offers

+ References

No definition available.

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- Definition

This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature.

+ References

No definition available.

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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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- 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.

+ References

No definition available.

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

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

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

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- Definition

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

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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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- Definition

Interest received on loans and other debt instruments during the current period.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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Debt - Public Debt (Details)		1 Months Ended	2 Months Ended	3 Months Ended		12 Months Ended
Debt - Public Debt (Details)	Oct. 02, 2017 shares	Sep. 30, 2014 shares	May 31, 2017 USD ($) $ / shares shares	Mar. 31, 2018 USD ($)	Jun. 30, 2017 USD ($) cash_tender_offer $ / shares shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Cash paid to holders of debt instrument, net					$ 409,000,000
Common stock sold (in shares) \| shares	24,022	25,000,000			12,958,767
Common stock sold per share (usd per share) \| $ / shares					$ 35.91
Debt instrument, repurchase amount					$ 874,000,000
Interest charge related to early redemption of notes					58,000,000
Interest paid					27,000,000
Legal fees					2,000,000
Pre-tax gain on sale of common stock					167,000,000	$ 167,000,000
Interest expense					24,000,000	$ 378,000,000	$ 496,000,000	$ 499,000,000
Interest Rate Swap
Debt Instrument [Line Items]
Proceeds from interest received					8,000,000
Investment Banks
Debt Instrument [Line Items]
Debt instrument, face amount					$ 805,000,000
Number of cash tender offers \| cash_tender_offer					3
Common stock sold (in shares) \| shares			12,958,767
Common stock sold per share (usd per share) \| $ / shares			$ 35.91
Pre-tax gain on sale of common stock			$ 167,000,000
Investment Banks \| Maximum
Debt Instrument [Line Items]
Debt instrument, face amount					$ 1,000,000,000
5.72% Notes, due 2019
Debt Instrument [Line Items]
Convertible notes, interest rate percentage				5.72%		5.72%
Debt instrument, face amount				$ 500,000,000
Debt instrument redemption amount				518,000,000
Loss on extinguishment of debt				$ 19,000,000
5.72% Notes, due 2019 \| Investment Banks
Debt Instrument [Line Items]
Debt instrument, face amount					$ 250,000,000
6.50% Bonds, due 2018
Debt Instrument [Line Items]
Convertible notes, interest rate percentage					6.50%	6.50%
Debt instrument, face amount					$ 100,000,000
6.50% Bonds, due 2018 \| Investment Banks
Debt Instrument [Line Items]
Debt instrument, face amount					$ 150,000,000
6.75% Notes, due 2018
Debt Instrument [Line Items]
Convertible notes, interest rate percentage					6.75%	6.75%
Debt instrument, face amount					$ 345,000,000
Debt instrument redemption amount					479,000,000
6.75% Notes, due 2018 \| Investment Banks
Debt Instrument [Line Items]
Debt instrument, face amount					$ 405,000,000