Other Noncurrent Assets - Additional Information (Detail) $ in Millions	1 Months Ended
Jan. 31, 2016 USD ($)
Fuhu Inc. and Sproutling Inc.
Other Noncurrent Assets Disclosure [Line Items]
Amortizable identifiable intangible assets acquired	$ 11.2

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration