AMAK INVENTORIES (Details) $ in Thousands	Dec. 31, 2018 USD ($)	Dec. 31, 2018 SAR (ر.س)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 SAR (ر.س)
Inventory [Line Items]
Inventories \| $	$ 16,539		$ 18,450
AMAK
Inventory [Line Items]
Inventories		ر.س 45,871,120		ر.س 27,226,932
AMAK \| Ore concentrates
Inventory [Line Items]
Inventories		17,020,657		12,118,132
AMAK \| Stockpile ore
Inventory [Line Items]
Inventories		19,134,297		9,417,626
AMAK \| Precious metal dore
Inventory [Line Items]
Inventories		2,159,192		0
AMAK \| Explosives
Inventory [Line Items]
Inventories		1,134,728		485,668
AMAK \| Chemicals and other
Inventory [Line Items]
Inventories		ر.س 6,422,246		ر.س 5,205,506