Contractual Maturities of Available-for-Sale Securities (Detail) $ in Thousands	Jun. 30, 2018 USD ($)
Amortized Cost
Within 1 year	$ 46,698
After 1 year through 5 years	0
After 5 years through 10 years	0
After 10 years	5,942
Total	52,640
Fair Value
Within 1 year	46,698
After 1 year through 5 years	0
After 5 years through 10 years	0
After 10 years	5,662
Total	$ 52,360

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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