Summary of Available for Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013
Schedule Of Short Term Investments And Available For Sale Securities [Line Items]
Amortized cost	$ 32,917
Gross unrealized gains	13
Gross unrealized losses	(8)
Fair value	32,922
U.S. government-related debt securities
Schedule Of Short Term Investments And Available For Sale Securities [Line Items]
Amortized cost	1,581
Gross unrealized gains	2
Fair value	1,583
Corporate debt securities
Schedule Of Short Term Investments And Available For Sale Securities [Line Items]
Amortized cost	31,336
Gross unrealized gains	11
Gross unrealized losses	(8)
Fair value	$ 31,339

Available For Sale Securities Gross Unrealized Gains Accumulated In Investments

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- Definition

Amount of accumulated pre-tax unrealized loss before deducting pre-tax unrealized gain on investments in available-for-sale securities impacting investments.

+ References

No definition available.

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This item represents the cost of debt and equity 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 210

-SubTopic 10

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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