Note 4 - Accounts Receivable, Net (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accounts Receivable, Credit Loss Expense (Reversal)	$ 192	$ 481
Internet Advertising and TV Advertising [Member]
Accounts Receivable, Allowance for Credit Loss, Writeoff	$ 3,700	3,400
Number of Months Past Due	180 days
Accounts Receivable, Credit Loss Expense (Reversal)	$ 190	$ 470

Reflected the number of months past due of the proportion of accounts receivable which allowance for doubtful debts has been provided.

No definition available.

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

+ Details

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

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(5))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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- Details

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