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
-Section 13
-Sentence Column B

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ 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

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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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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Derivative Instruments (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
Derivative Instruments (Narrative) (Details) - USD ($)	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Net assets associated with foreign currency derivatives	$ 6,000,000		$ 6,000,000		$ (8,800,000)
Maturity period of derivatives (in months)			18 months
Estimated amount of net gains (losses) associated with derivative instruments, net of tax, in next twelve months			$ 3,300,000
Designated as Hedging Instrument \| Foreign Exchange Forward \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	164,000,000		164,000,000
Designated as Hedging Instrument \| United Kingdom, Pounds \| Foreign Exchange Forward \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	74,400,000		74,400,000
Designated as Hedging Instrument \| Australia, Dollars \| Foreign Exchange Forward \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	33,800,000		33,800,000
Designated as Hedging Instrument \| Euro Member Countries, Euro \| Foreign Exchange Forward \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	23,300,000		23,300,000
Designated as Hedging Instrument \| Brazil, Brazil Real \| Foreign Exchange Forward \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	20,300,000		20,300,000
Designated as Hedging Instrument \| No currency \| Foreign Exchange Forward \| Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	12,200,000		12,200,000
Not Designated
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses) on derivatives not designated as hedging instruments	2,700,000	$ (400,000)	8,900,000	$ 500,000
Not Designated \| Foreign Exchange Forward \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	137,100,000		137,100,000
Not Designated \| United Kingdom, Pounds \| Foreign Exchange Forward \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	12,300,000		12,300,000
Not Designated \| Australia, Dollars \| Foreign Exchange Forward \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	7,700,000		7,700,000
Not Designated \| Euro Member Countries, Euro \| Foreign Exchange Forward \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	94,400,000		94,400,000
Not Designated \| Brazil, Brazil Real \| Foreign Exchange Forward \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	10,100,000		10,100,000
Not Designated \| No currency \| Foreign Exchange Forward \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	$ 12,600,000		$ 12,600,000