Guarantor Financial Statements (Unaudited) Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of year	$ 2,512	$ 4,823	$ 2,512	$ 4,823	$ 4,455	$ 4,710
Cash flow from operating activities:
Net cash provided by operating activities			1,312	3,925
Cash flow from investing activities:
Capital expenditures	(666)	(507)	(1,917)	(1,391)
Intercompany loans			0	0
Dividends from (investments in) consolidated subsidiaries			(2)	0
Proceeds From Divestiture Of Business And Interests In Affiliates And Proceeds From Sale Of Other Assets			94	(81)
Net cash used in investing activities			(1,825)	(1,472)
Cash flow from financing activities:
Proceeds from debt			1,681	475
Repayments of debt			(2,917)	(2,410)
Intercompany loans			0	0
Cash dividends paid and contributions received, net			(164)	(386)
Other, net			(30)	(19)
Net cash used in financing activities			(1,430)	(2,340)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect			(1,943)	113
Eliminations [Member]
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of year	0	0	0	0	0	0
Cash flow from operating activities:
Net cash provided by operating activities			0	0
Cash flow from investing activities:
Capital expenditures			0	0
Intercompany loans			801	558
Dividends from (investments in) consolidated subsidiaries			(1,769)	(2,791)
Proceeds From Divestiture Of Business And Interests In Affiliates And Proceeds From Sale Of Other Assets			0	0
Net cash used in investing activities			(968)	(2,233)
Cash flow from financing activities:
Proceeds from debt			0	0
Repayments of debt			0	0
Intercompany loans			(802)	(558)
Cash dividends paid and contributions received, net			1,750	2,775
Other, net			20	16
Net cash used in financing activities			968	2,233
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect			0	0
Reportable Legal Entities [Member] | FCX Issuer [Member]
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of year	0	0	0	0	0	0
Cash flow from operating activities:
Net cash provided by operating activities			352	(181)
Cash flow from investing activities:
Capital expenditures			0	(2)
Intercompany loans			(801)	(558)
Dividends from (investments in) consolidated subsidiaries			1,697	2,726
Proceeds From Divestiture Of Business And Interests In Affiliates And Proceeds From Sale Of Other Assets			(1)	4
Net cash used in investing activities			895	2,170
Cash flow from financing activities:
Proceeds from debt			1,200	0
Repayments of debt			(2,202)	(1,826)
Intercompany loans			0	0
Cash dividends paid and contributions received, net			(218)	(145)
Other, net			(27)	(18)
Net cash used in financing activities			(1,247)	(1,989)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect			0	0
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of year	0	0	0	0	0	7
Cash flow from operating activities:
Net cash provided by operating activities			(326)	(285)
Cash flow from investing activities:
Capital expenditures			(4)	0
Intercompany loans			0	0
Dividends from (investments in) consolidated subsidiaries			0	0
Proceeds From Divestiture Of Business And Interests In Affiliates And Proceeds From Sale Of Other Assets			98	3
Net cash used in investing activities			94	3
Cash flow from financing activities:
Proceeds from debt			0	0
Repayments of debt			0	(52)
Intercompany loans			232	327
Cash dividends paid and contributions received, net			0	0
Other, net			0	0
Net cash used in financing activities			232	275
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect			0	(7)
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of year	$ 2,512	$ 4,823	2,512	4,823	$ 4,455	$ 4,703
Cash flow from operating activities:
Net cash provided by operating activities			1,286	4,391
Cash flow from investing activities:
Capital expenditures			(1,913)	(1,389)
Intercompany loans			0	0
Dividends from (investments in) consolidated subsidiaries			70	65
Proceeds From Divestiture Of Business And Interests In Affiliates And Proceeds From Sale Of Other Assets			(3)	(88)
Net cash used in investing activities			(1,846)	(1,412)
Cash flow from financing activities:
Proceeds from debt			481	475
Repayments of debt			(715)	(532)
Intercompany loans			570	231
Cash dividends paid and contributions received, net			(1,696)	(3,016)
Other, net			(23)	(17)
Net cash used in financing activities			(1,383)	(2,859)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect			$ (1,943)	$ 120