Fair Value of Financial Instruments - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 500	$ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	500
Fair Value, Measurements, Recurring \| Fair Value
Assets:
Fair value measurement disclosure	78,350	47,552
Fair Value, Measurements, Recurring \| Operating cash \| Fair Value
Assets:
Fair value measurement disclosure	47,586	47,287
Fair Value, Measurements, Recurring \| Certificates of Deposit [Member] \| Fair Value
Assets:
Fair value measurement disclosure	30,000
Fair Value, Measurements, Recurring \| Restricted cash \| Fair Value
Assets:
Fair value measurement disclosure	264	265
Fair Value, Measurements, Recurring \| Cost-method Investments [Member] \| Fair Value
Assets:
Fair value measurement disclosure	500
Fair Value, Measurements, Recurring \| Level 1
Assets:
Fair value measurement disclosure	47,850	47,552
Fair Value, Measurements, Recurring \| Level 1 \| Operating cash
Assets:
Fair value measurement disclosure	47,586	47,287
Fair Value, Measurements, Recurring \| Level 1 \| Certificates of Deposit [Member]
Assets:
Fair value measurement disclosure	0
Fair Value, Measurements, Recurring \| Level 1 \| Restricted cash
Assets:
Fair value measurement disclosure	264	265
Fair Value, Measurements, Recurring \| Level 1 \| Cost-method Investments [Member]
Assets:
Fair value measurement disclosure	0
Fair Value, Measurements, Recurring \| Level 2
Assets:
Fair value measurement disclosure	30,000	0
Fair Value, Measurements, Recurring \| Level 2 \| Operating cash
Assets:
Fair value measurement disclosure	0	0
Fair Value, Measurements, Recurring \| Level 2 \| Certificates of Deposit [Member]
Assets:
Fair value measurement disclosure	30,000
Fair Value, Measurements, Recurring \| Level 2 \| Restricted cash
Assets:
Fair value measurement disclosure	0	0
Fair Value, Measurements, Recurring \| Level 2 \| Cost-method Investments [Member]
Assets:
Fair value measurement disclosure	0
Fair Value, Measurements, Recurring \| Level 3
Assets:
Fair value measurement disclosure	500	0
Fair Value, Measurements, Recurring \| Level 3 \| Operating cash
Assets:
Fair value measurement disclosure	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Certificates of Deposit [Member]
Assets:
Fair value measurement disclosure	0
Fair Value, Measurements, Recurring \| Level 3 \| Restricted cash
Assets:
Fair value measurement disclosure	0	$ 0
Fair Value, Measurements, Recurring \| Level 3 \| Cost-method Investments [Member]
Assets:
Fair value measurement disclosure	$ 500

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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