Amortized Cost and Fair Value of Investments by Contractual Maturity (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Amortized cost
Debt securities due within one year	$ 15,132
Debt securities due within one to five years	23,951
Debt securities due within five years or more	3,379
Total	42,462
Fair value
Debt securities due within one year	15,147
Debt securities due within one to five years	24,040
Debt securities due within five years or more	3,466
Total	$ 42,653

Available for sale Securities, Debt Maturities, after Five Years, Amortized Cost

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This item represents the fair value of debt securities which are expected to mature after five years from the balance sheet date which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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Available For Sale Securities Debt Maturities Fair Value Total

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth 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 any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at cost, net of adjustments, 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 any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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