Significant Accounting Policies - Investments in Venezuelan Bonds (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Total investments	$ 2,835
Investments in Venezuelan bonds, Market Value	2,835
Venezuelan bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Total investments	2,835
Investments in Venezuelan bonds, Gross Unrealized Gain
Investments in Venezuelan bonds, Gross Unrealized Loss
Investments in Venezuelan bonds, Net Unrealized Gain
Investments in Venezuelan bonds, Market Value	$ 2,835

Available For Sale Debt Securities Net Unrealized Gain Loss Accumulated In Investments

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 2

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-SubTopic 10

-Section S99

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Topic 942

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-Subparagraph (b)-(g)

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