Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisitions - Summary of Preliminary Allocation of Purchase Price and Estimated Useful Lives of Identifiable Assets Acquired (Detail) - USD ($) $ in Thousands	Oct. 01, 2018	Mar. 31, 2019	Jun. 30, 2018
Business Acquisition [Line Items]
Goodwill		$ 67,429	$ 62,283
AmOne Corp [Member]
Business Acquisition [Line Items]
Goodwill	$ 5,146
Total purchase price	30,684
AmOne Corp [Member] \| Customer/publisher/advertiser relationships [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 21,300
Estimated Useful Life	7 years
AmOne Corp [Member] \| Website/trade/domain names [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 900
Estimated Useful Life	15 years
AmOne Corp [Member] \| Acquired technology and others [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 500
Estimated Useful Life	3 years
AmOne Corp [Member] \| Net assets [Member]
Business Acquisition [Line Items]
Estimated Fair Value	$ 2,838
Estimated Useful Life	0 years