XML 121 R93.htm IDEA: XBRL DOCUMENT v3.20.2
EMPLOYEE BENEFIT PLANS (Assumed Health Care Cost Trend Rates) (Detail) - Post Retirement Medical Plan [Member]
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]    
Health care cost trend rate assumed for next year 5.70% 5.80%
Rate to which the cost trend rate was assumed to decline (the ultimate trend rate) 4.50% 4.50%
Year that the rate reaches the ultimate trend rate 2038 2038