Foreign Currency Hedging (Schedule of Foreign Currency Exchange Contracts Designated as Cash Flow Hedges) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivative [Line Items]
Derivative, Notional Amount	$ 85,875invest_DerivativeNotionalAmount	$ 111,614invest_DerivativeNotionalAmount
Fair Value	4,069	(8,871)
Eurodollar Sell Forward Contract 1.240 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.240
Derivative, Notional Amount	0	10,850
Fair Value	0	(1,207)
Eurodollar Sell Forward Contract 1.256 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.256
Derivative, Notional Amount	6,000	0
Fair Value	241	0
Eurodollar Sell Forward Contract 1.257 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.257
Derivative, Notional Amount	15,750	0
Fair Value	728	0
Eurodollar Sell Forward Contract 1.259 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.259
Derivative, Notional Amount	16,125	0
Fair Value	752	0
Eurodollar Sell Forward Contract 1.260 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.260
Derivative, Notional Amount	33,000	0
Fair Value	1,468	0
Eurodollar Sell Forward Contract 1.270 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.270
Derivative, Notional Amount	7,000	44,450
Fair Value	377	(3,760)
Eurodollar Sell Forward Contract 1.281 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.281
Derivative, Notional Amount	8,000	36,814
Fair Value	503	(2,785)
Eurodollar Sell Forward Contract 1.300 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.300
Derivative, Notional Amount	0	19,500
Fair Value	$ 0	$ (1,119)

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

Contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of all foreign currency derivatives designated as cash flow 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 4B

-Subparagraph (a),(b),(c)(1)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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