Contractual Maturities of Marketable Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Due in 1 year or less	$ 16,478
Due in 1 to 2 years	1,217
Amortized Cost	17,695	$ 19,326
Due in 1 year or less	16,482
Due in 1 to 2 years	1,217
Fair Value	$ 17,699	$ 19,315

Available for Sale Securities, Debt Maturities, after One Through Two Years, Fair Value

No definition available.

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- Definition

Available for sale Securities, Debt Maturities, One Through Two Years, Amortized Cost

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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-Publisher FASB
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+ References

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-Publisher FASB
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-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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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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