Financial Derivatives - Deferred Gains (Losses) and Related Taxes on Cash Flow Hedges (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Deferred gains (losses) in AOCI	$ (163)	$ (1,825)
Tax on deferred gains (losses) in AOCI	(29)	(39)
Deferred gains (losses) in AOCI, net of taxes	(192)	$ (1,864)
Deferred gains (losses) expected to be reclassified to "Revenues" from AOCI during the next twelve months	$ (163)

The total deferred gains (losses) on derivatives designated as cash flow hedges, before tax, included within accumulated other comprehensive income.

No definition available.

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- Definition

The total deferred gains (losses) on derivatives designated as cash flow hedges, net of tax, included within accumulated other comprehensive income.

+ References

No definition available.

+ Details

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- Definition

The total tax on the deferred gains (losses) on derivatives designated as cash flow hedges included within accumulated other comprehensive income.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80845-113994

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