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

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

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

+ References

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- Definition

Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated 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 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959

Reference 2: 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=35706170&loc=SL5624171-113959

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Derivative Instruments and Hedging Activities - Additional Information (Detail) € in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2015 EUR (€)	Dec. 31, 2015 USD ($)	Mar. 31, 2015 USD ($)	Sep. 30, 2014 USD ($)
2010 Senior Notes [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount					$ 250.0
2014 Senior Notes (5-Year) [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount				$ 200.0
2015 Senior Notes [Member] \| Cross-Currency Swap [Member] \| Derivatives Not Designated as Investment Hedges [Member]
Derivative [Line Items]
Notional amount \| €		€ 100.0
2015 Senior Notes [Member] \| Cross-Currency Swap [Member] \| Currency Paid [Member] \| Derivatives Not Designated as Investment Hedges [Member]
Derivative [Line Items]
Derivative, swaption interest rate		1.75%	1.75%
2015 Senior Notes [Member] \| Cross-Currency Swap [Member] \| Currency Received [Member] \| Derivatives Not Designated as Investment Hedges [Member]
Derivative [Line Items]
Gain due to termination of Interest rate swap	$ 110.5
Derivative, swaption interest rate		3.945%	3.945%
2014 Senior Notes (30-Year) [Member] \| Treasury Rate Lock [Member]
Derivative [Line Items]
Notional amount			$ 150.0
Gain due to termination of Interest rate swap	$ 1.1
Net Investment Hedging [Member] \| 2015 Senior Notes [Member] \| Derivatives Designated as Accounting Hedges [Member]
Derivative [Line Items]
Notional amount \| €		€ 400.0