Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-SubTopic 10
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The portion of losses on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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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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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Financial Instruments, Hedging Activities and Fair Value Measurements (Cash Flow and Net Investment Hedges) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Feb. 28, 2018
Derivatives, Fair Value [Line Items]
Notional amount	$ 560,000,000
Ineffective portion of expense	1,000,000
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Notional amount				$ 525,000,000
Currency Swap [Member]
Derivatives, Fair Value [Line Items]
Notional amount				$ 575,000,000
Fair Value Hedging [Member] \| Interest Rate Swap [Member] \| Interest Expense [Member]
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount	0
Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	0	$ (6,000,000)
Gain (Loss) Recognized Amount	5,000,000	2,000,000
Cash Flow Hedging [Member] \| Foreign currency contracts [Member]
Derivatives, Fair Value [Line Items]
Notional amount	69,000,000		$ 50,000,000
Cash Flow Hedging [Member] \| Foreign currency contracts [Member] \| Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	0	(6,000,000)
Gain (Loss) Recognized Amount	(1,000,000)	(3,000,000)
Net Investment Hedging [Member]
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	70,000,000	(94,000,000)
Gain (Loss) Recognized Amount	4,000,000	1,000,000
Net Investment Hedging [Member] \| Currency Swap [Member]
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	13,000,000	(26,000,000)
Gain (Loss) Recognized Amount	4,000,000	1,000,000
Net Investment Hedging [Member] \| Other Foreign Currency Denominated Debt [Member]
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI	57,000,000	(68,000,000)
Not Designated as Hedging Instrument \| Foreign currency contracts [Member] \| Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount	$ 6,000,000	$ 4,000,000