Derivatives and Hedging Activities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Cash collateral netting, Liabilities	$ 0.0	$ (49.0)
Cash collateral netting, Assets	0.0	(2.0)
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset and derivative liability netting	(26.0)	(27.0)
Total derivatives assets, net	37.0	272.0
Other Assets [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	54.0	173.0
Other Assets [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	9.0	128.0
Other Assets [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	0.0	22.0
Other Assets [Member] \| Net Investment Hedging [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative assets	54.0	151.0
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset and derivative liability netting	(26.0)	(27.0)
Total derivatives liabilities, net	69.0	22.0
Other Liabilities [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	38.0	70.0
Other Liabilities [Member] \| Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	57.0	28.0
Other Liabilities [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	0.0	69.0
Other Liabilities [Member] \| Net Investment Hedging [Member] \| Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total fair value of derivative liabilities	$ 38.0	$ 1.0

Represents the netting of derivative assets and liabilities under master netting agreements.

No definition available.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

+ References

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
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-Subparagraph (c)
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-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

+ References

+ Details

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ 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.

+ References

No definition available.

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