Note 22 - Segment Reporting - Summary of Segment Reporting Information (Details) - USD ($) $ in Thousands	3 Months Ended						6 Months Ended
	Jun. 30, 2019		Mar. 31, 2019	Jun. 30, 2018		Mar. 31, 2018	Jun. 30, 2019		Jun. 30, 2018		Dec. 31, 2018
Revenues	$ 15,453			$ 22,520			$ 24,020		$ 30,780
Cost of revenues	15,087			21,552			23,212		29,211
Total operating expenses	1,588			9,288			2,768		11,434
Depreciation and amortization expense included in total operating expenses	14			211			52		427
Operating (loss)/income	(1,222)			(8,320)			(1,960)		(9,865)
Change in fair value of warrant liabilities	821			(526)			471		948
Net (loss)/income	(382)		$ (1,140)	(9,554)		$ (570)	(1,522)		(10,124)
Total assets	14,671						14,671				$ 16,968
Impairment on goodwill included in total operating expenses				5,412					5,412
Impairment on intangible assets included in total operating expenses				1,878					1,878
Impairment on long-term investments									(471)
Net (loss)/income	(382)		$ (1,140)	(9,554)		$ (570)	(1,522)		(10,124)
Expenditure for long-term assets				2,556					4,205
Corporate, Non-Segment [Member]
Revenues									371
Cost of revenues
Total operating expenses	419	[1]		493	[2]		871	[3]	1,366	[4]
Depreciation and amortization expense included in total operating expenses	1			19			16		38
Operating (loss)/income	(419)			(493)			(871)		(995)
Change in fair value of warrant liabilities	821			(526)			471		948
Net (loss)/income	401			(1,338)			(400)		(855)
Total assets	16,143						16,143				17,155
Impairment on goodwill included in total operating expenses
Impairment on intangible assets included in total operating expenses
Impairment on long-term investments									(471)
Net (loss)/income	401			(1,338)			(400)		(855)
Expenditure for long-term assets				1					2
Intersegment Eliminations [Member]
Revenues									(371)
Cost of revenues
Total operating expenses									(371)
Depreciation and amortization expense included in total operating expenses
Operating (loss)/income
Change in fair value of warrant liabilities
Net (loss)/income
Total assets	(16,640)						(16,640)				(16,546)
Impairment on goodwill included in total operating expenses
Impairment on intangible assets included in total operating expenses
Impairment on long-term investments
Net (loss)/income
Expenditure for long-term assets
Internet Ad [Member] | Operating Segments [Member]
Revenues	15,453			22,520			24,020		30,689
Cost of revenues	15,087			21,552			23,212		29,173
Total operating expenses	1,145			8,766			1,850		10,388
Depreciation and amortization expense included in total operating expenses	12			192			35		389
Operating (loss)/income	(779)			(7,798)			(1,042)		(8,872)
Change in fair value of warrant liabilities
Net (loss)/income	(760)			(8,198)			(1,075)		(9,271)
Total assets	11,550						11,550				12,756
Impairment on goodwill included in total operating expenses				5,412					5,412
Impairment on intangible assets included in total operating expenses				1,878					1,878
Impairment on long-term investments
Net (loss)/income	(760)			(8,198)			(1,075)		(9,271)
Expenditure for long-term assets									448
TV Ad [Member] | Operating Segments [Member]
Revenues									91
Cost of revenues									38
Total operating expenses	18			25			36		47
Depreciation and amortization expense included in total operating expenses
Operating (loss)/income	(18)			(25)			(36)		6
Change in fair value of warrant liabilities
Net (loss)/income	(17)			(14)			(36)		6
Total assets	229						229				207
Impairment on goodwill included in total operating expenses
Impairment on intangible assets included in total operating expenses
Impairment on long-term investments
Net (loss)/income	(17)			(14)			(36)		6
Expenditure for long-term assets
Blockchain Technology [Member] | Operating Segments [Member]
Revenues
Cost of revenues
Total operating expenses	6			4			11		4
Depreciation and amortization expense included in total operating expenses	1						1
Operating (loss)/income	(6)			(4)			(11)		(4)
Change in fair value of warrant liabilities
Net (loss)/income	(6)			(4)			(11)		(4)
Total assets	3,389						3,389				$ 3,396
Impairment on goodwill included in total operating expenses
Impairment on intangible assets included in total operating expenses
Impairment on long-term investments
Net (loss)/income	$ (6)			(4)			$ (11)		(4)
Expenditure for long-term assets				$ 2,555					$ 3,755

[1] Including approximately US$102,000 share-based compensation expenses.

[2] Including approximately US$76,000 share-based compensation expenses.

[3] Including approximately US$203,000 share-based compensation expenses.

[4] Including approximately US$151,000 share-based compensation expenses.