Assets held for sale and discontinued operations - Summarized operating results for discontinued operations (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating results
Revenue	$ 0	$ 0	$ 600,000
Losses before tax, gain on sales and impairment	1,032,000	(1,534,000)	(3,069,000)
Losses before tax	1,032,000	(1,534,000)	(3,069,000)
Tax provision	0	0	(713,000)
Net losses from discontinued operations	1,032,000	(1,534,000)	(3,782,000)
Ubud Hanging Gardens
Discontinued operations
Legal fees		636,000	1,486,000
Operating results
Revenue	0	0	0
Losses before tax, gain on sales and impairment	69,000	(636,000)	(1,486,000)
Losses before tax	69,000	(636,000)	(1,486,000)
Tax provision			(713,000)
Net losses from discontinued operations	69,000	(636,000)	(2,199,000)
Porto Cupecoy
Operating results
Revenue	0	0	600,000
Losses before tax, gain on sales and impairment	963,000	(898,000)	(1,583,000)
Losses before tax	963,000	(898,000)	(1,583,000)
Tax provision			0
Net losses from discontinued operations	$ 963,000	$ (898,000)	$ (1,583,000)