Guarantor Financial Statements (Unaudited) Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Cash flow from operating activities:
Net cash provided by operating activities	$ 792	$ 740
Cash flow from investing activities:
Capital expenditures	(344)	(982)
Intercompany loans	0	0
Dividends from (investments in) consolidated subsidiaries	0	0
Asset sales and other, net	(21)	2
Net cash provided by (used in) investing activities	(365)	(980)
Cash flow from financing activities:
Proceeds from debt	157	1,796
Repayments of debt	(815)	(1,442)
Intercompany loans	0	0
Proceeds from Issuance of Common Stock	0	32
Cash dividends paid and contributions received, net	(16)	(22)
Other, net	(5)	(17)
Net cash (used in) provided by financing activities	(679)	347
Net (decrease) increase in cash and cash equivalents	(252)	107
Increase (Decrease) In Cash And Cash Equivalents In Assets Held For Sale	8	(53)
Cash and cash equivalents at beginning of year	4,245	177
Cash and cash equivalents at end of period	4,001	231
Eliminations [Member]
Cash flow from operating activities:
Net cash provided by operating activities	0	5
Cash flow from investing activities:
Capital expenditures	0	(2)
Intercompany loans	277	938
Dividends from (investments in) consolidated subsidiaries	(920)	(352)
Asset sales and other, net	0	0
Net cash provided by (used in) investing activities	(643)	584
Cash flow from financing activities:
Proceeds from debt	0	0
Repayments of debt	0	0
Intercompany loans	(277)	(938)
Proceeds from Issuance of Common Stock		(42)
Cash dividends paid and contributions received, net	880	355
Other, net	40	36
Net cash (used in) provided by financing activities	643	(589)
Net (decrease) increase in cash and cash equivalents	0	0
Increase (Decrease) In Cash And Cash Equivalents In Assets Held For Sale	0	0
Cash and cash equivalents at beginning of year	0	0
Cash and cash equivalents at end of period	0	0
Reportable Legal Entities [Member] \| FCX Issuer [Member]
Cash flow from operating activities:
Net cash provided by operating activities	(112)	(117)
Cash flow from investing activities:
Capital expenditures	0	0
Intercompany loans	(277)	(561)
Dividends from (investments in) consolidated subsidiaries	894	358
Asset sales and other, net	0	0
Net cash provided by (used in) investing activities	617	(203)
Cash flow from financing activities:
Proceeds from debt	0	1,060
Repayments of debt	(499)	(750)
Intercompany loans	0	0
Proceeds from Issuance of Common Stock		32
Cash dividends paid and contributions received, net	(1)	(4)
Other, net	(5)	(18)
Net cash (used in) provided by financing activities	(505)	320
Net (decrease) increase in cash and cash equivalents	0	0
Increase (Decrease) In Cash And Cash Equivalents In Assets Held For Sale	0	0
Cash and cash equivalents at beginning of year	0	0
Cash and cash equivalents at end of period	0	0
Reportable Legal Entities [Member] \| Guarantor Subsidiaries [Member]
Cash flow from operating activities:
Net cash provided by operating activities	(200)	(32)
Cash flow from investing activities:
Capital expenditures	(10)	(244)
Intercompany loans	0	(377)
Dividends from (investments in) consolidated subsidiaries	0	(41)
Asset sales and other, net	(23)	2
Net cash provided by (used in) investing activities	(33)	(660)
Cash flow from financing activities:
Proceeds from debt	0	0
Repayments of debt	0	0
Intercompany loans	236	716
Proceeds from Issuance of Common Stock		0
Cash dividends paid and contributions received, net	0	0
Other, net	(6)	(24)
Net cash (used in) provided by financing activities	230	692
Net (decrease) increase in cash and cash equivalents	(3)	0
Increase (Decrease) In Cash And Cash Equivalents In Assets Held For Sale	0	0
Cash and cash equivalents at beginning of year	3	0
Cash and cash equivalents at end of period	0	0
Reportable Legal Entities [Member] \| Non-Guarantor Subsidiaries [Member]
Cash flow from operating activities:
Net cash provided by operating activities	1,104	884
Cash flow from investing activities:
Capital expenditures	(334)	(736)
Intercompany loans	0	0
Dividends from (investments in) consolidated subsidiaries	26	35
Asset sales and other, net	2	0
Net cash provided by (used in) investing activities	(306)	(701)
Cash flow from financing activities:
Proceeds from debt	157	736
Repayments of debt	(316)	(692)
Intercompany loans	41	222
Proceeds from Issuance of Common Stock		42
Cash dividends paid and contributions received, net	(895)	(373)
Other, net	(34)	(11)
Net cash (used in) provided by financing activities	(1,047)	(76)
Net (decrease) increase in cash and cash equivalents	(249)	107
Increase (Decrease) In Cash And Cash Equivalents In Assets Held For Sale	8	(53)
Cash and cash equivalents at beginning of year	4,242	177
Cash and cash equivalents at end of period	$ 4,001	$ 231

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The net cash outflow or inflow from other investing activities, excluding investment in subsidiaries. This element is used when there is not a more specific and appropriate element in the taxonomy.

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The cash inflow or outflow associated with long-term loans for related parties where one party can exercise control or significant influence over another party, including affiliates, owners or officers and their immediate families, pension trusts, and so forth. This concept relates to payments that are investing activities.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow or outflow associated with long-term loans for related parties where one party can exercise control or significant influence over another party, including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from (Payments for) Advances to Affiliates.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt and payment of capital lease obligations.

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