Derivative Instruments and Hedging - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($) payment $ / bbl	Dec. 31, 2015 USD ($)
Derivative [Line Items]
Number of contingent payments | payment	2
Freeport Mc Mo Ran Inc [Member]
Derivative [Line Items]
Derivative contingent settlement period	12 months
Freeport Mc Mo Ran Inc [Member] | Other Assets [Member]
Derivative [Line Items]
Estimated fair value of these contingent payments	$ 14,400,000	$ 0
Freeport Mc Mo Ran Inc [Member] | Noble Corp [Member]
Derivative [Line Items]
Contract drilling services revenue	$ 14,400,000
Freeport Mc Mo Ran Inc [Member] | WTI Crude Oil Averages Price More than $50 Per Barrel [Member]
Derivative [Line Items]
Crude oil average price (usd per barrel) | $ / bbl	50
Non designated derivatives contingent payment	$ 25,000,000
Freeport Mc Mo Ran Inc [Member] | WTI Crude Oil Averages Price More than $65 Per Barrel [Member]
Derivative [Line Items]
Crude oil average price (usd per barrel) | $ / bbl	65
Non designated derivatives contingent payment	$ 50,000,000
Forward contracts [Member]
Derivative [Line Items]
Derivative instruments settled	53,000,000	88,000,000
Derivative contracts [Member]
Derivative [Line Items]
Notional amount of forward contracts outstanding	$ 0	$ 0