Property, plant and equipment, net (Tables)

12 Months Ended

Mar. 31, 2019

Property, Plant and Equipment [Abstract]

Property, plant and equipment, net

	March 31,
	2018			2019
	$ in thousands			$ in thousands
Cost
Buildings		17,863			16,890
Construction-in-progress		260			597
Plant and machinery		9,932			9,838
Furniture, fixtures and equipment		1,468			1,475
Motor vehicles		643			636
		30,166			29,436
Less: accumulated depreciation		(19,732	)		(19,845	)
		10,434			9,591