COMMITMENTS AND CONTINGENCIES: - Guaymas sulfuric acid spill (Details) - Marine Terminal in Guaymas		9 Months Ended
Jul. 09, 2019 m³	Sep. 30, 2019 item
SUBSEQUENT EVENTS:
Volume of sulfuric acid discharged in the incident at Guaymas	3
Water volume at Guaymas bay	340,000,000
Number of times of renewal \| item		4
Number of years of each renewal		2 years

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration