Weyerhaeuser (WY) 10-K 14 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) shares in Thousands, $ in Billions	12 Months Ended
	Dec. 31, 2019	Feb. 03, 2020	Jun. 30, 2019
Cover [Abstract]
Entity Registrant Name	WEYERHAEUSER COMPANY
Trading Symbol	WY
Entity Central Index Key	0000106535
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Small Business	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		745,519
Entity Public Float			$ 19.6
Entity Shell Company	false
Entity File Number	1-4825
Entity Incorporation, State or Country Code	WA
Entity Tax Identification Number	91-0470860
Entity Address, Address Line One	220 OCCIDENTAL AVENUE SOUTH
Entity Address, City or Town	SEATTLE
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98104-7800
City Area Code	(206)
Local Phone Number	539-3000
Document Annual Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Shares ($1.25 par value)
Security Exchange Name	NYSE
Documents Incorporated by Reference	Portions of the Notice of 2020 Annual Meeting of Shareholders and Proxy Statement for the company’s Annual Meeting of Shareholders to be held May 15, 2020, are incorporated by reference into Part II and III

CONSOLIDATED STATEMENT OF OPERA

CONSOLIDATED STATEMENT OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Net sales	$ 6,554	$ 7,476	$ 7,196
Costs of sales	5,412	5,592	5,298
Gross margin	1,142	1,884	1,898
Selling expenses	84	88	87
General and administrative expenses	348	318	310
Charges for integration and restructuring, closures and asset impairments (Note 18)	80	2	194
Charges (recoveries) for product remediation, net (Note 19)	(68)	0	290
Other operating costs (income), net (Note 20)	47	82	(114)
Operating income	651	1,394	1,131
Non-operating pension and other postretirement benefit costs (Note 9)	(516)	(272)	(62)
Interest income and other	30	60	40
Interest expense, net of capitalized interest	(378)	(375)	(393)
Earnings (loss) before income taxes	(213)	807	716
Income taxes (Note 21)	137	(59)	(134)
Net earnings (loss)	$ (76)	$ 748	$ 582
Basic and diluted earnings (loss) per share (Note 5):	$ (0.10)	$ 0.99	$ 0.77
Weighted average shares outstanding (in thousands) (Note 5):
Basic	745,897	754,556	753,085
Diluted	745,897	756,827	756,666

CONSOLIDATED STATEMENT OF COMPR

CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Comprehensive income:
Net earnings (loss)	$ (76)	$ 748	$ 582
Other comprehensive income (loss):
Foreign currency translation adjustments	26	(54)	32
Changes in unamortized actuarial loss, net of tax (expense) benefit of ($73) in 2019, ($235) in 2018 and $2 in 2017	225	733	(132)
Changes in unamortized net prior service credit, net of tax (expense) benefit of ($1) in 2019, $3 in 2018 and $2 in 2017	(3)	(7)	(5)
Unrealized gains on available-for-sale securities	0	0	2
Total comprehensive income	$ 172	$ 1,420	$ 479

CONSOLIDATED STATEMENT OF COM_2

CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Changes in unamortized actuarial loss, tax (expense) benefit	$ (73)	$ (235)	$ 2
Changes in unamortized net prior service credit, tax (expense) benefit	$ (1)	$ 3	$ 2

CONSOLIDATED BALANCE SHEET

CONSOLIDATED BALANCE SHEET - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 139	$ 334
Receivables, net	309	337
Receivables for taxes	98	137
Inventories (Note 6)	416	389
Assets held for sale (Note 4)	140	0
Prepaid expenses and other current assets	147	152
Current restricted financial investments held by variable interest entities (Note 8)	362	253
Total current assets	1,611	1,602
Property and equipment, net (Note 7)	1,969	1,857
Construction in progress	130	136
Timber and timberlands at cost, less depletion	11,929	12,671
Minerals and mineral rights, less depletion	281	294
Deferred tax assets (Note 21)	72	15
Other assets	414	312
Restricted financial investments held by variable interest entities (Note 8)	0	362
Total assets	16,406	17,249
Current liabilities:
Current maturities of long-term debt (Notes 12 and 13)	0	500
Current debt (nonrecourse to the company) held by variable interest entities (Note 8)	0	302
Borrowings on line of credit (Notes 11 and 13)	230	425
Accounts payable	246	222
Accrued liabilities (Note 10)	530	490
Total current liabilities	1,006	1,939
Long-term debt, net (Notes 12 and 13)	6,147	5,419
Deferred tax liabilities (Note 21)	6	43
Deferred pension and other postretirement benefits (Note 9)	693	527
Other liabilities	377	275
Commitments and contingencies (Note 14)
Total liabilities	8,229	8,203
Weyerhaeuser shareholders’ interest (Notes 15 and 16):
Common shares: $1.25 par value; authorized 1,360 million shares; issued and outstanding: 745,300 thousand shares at December 31, 2019 and 746,391 thousand shares at December 31, 2018	932	933
Other capital	8,152	8,172
Retained earnings (accumulated deficit)	(3)	1,093
Accumulated other comprehensive loss (Note 15)	(904)	(1,152)
Total equity	8,177	9,046
Total liabilities and equity	$ 16,406	$ 17,249

CONSOLIDATED BALANCE SHEET (Par

CONSOLIDATED BALANCE SHEET (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Common shares, par value	$ 1.25	$ 1.25
Common shares, authorized	1,360,000,000	1,360,000,000
Common shares, issued	745,300,000	746,391,000
Common shares, outstanding	745,300,000	746,391,000

CONSOLIDATED STATEMENT OF CASH

CONSOLIDATED STATEMENT OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operations:
Net earnings (loss)	$ (76)	$ 748	$ 582
Noncash charges (credits) to income:
Depreciation, depletion and amortization	510	486	521
Basis of real estate sold	116	124	81
Deferred income taxes, net (Note 21)	(169)	72	44
Pension and other postretirement benefits (Note 9)	548	309	97
Share-based compensation expense (Note 16)	30	42	40
Charges for impairment of assets (Note 18)	80	1	154
Net gains on sale of nonstrategic assets	(5)	(16)	(16)
Net gains on sale of nonstrategic timberlands (Notes 4 and 8)	(48)	0	(99)
Change in:
Receivables, less allowances	13	62	(35)
Receivable and payable for taxes	33	(103)	(50)
Inventories	(23)	(14)	(39)
Prepaid expenses and other current assets	6	(18)	(12)
Accounts payable and accrued liabilities	37	(154)	106
Pension and postretirement contributions / benefit payments	(45)	(381)	(78)
Other	(41)	(46)	(95)
Net cash from operations	966	1,112	1,201
Cash flows from investing activities:
Capital expenditures for property and equipment	(327)	(368)	(358)
Capital expenditures for timberlands reforestation	(57)	(59)	(61)
Proceeds from note receivable held by variable interest entities (Note 8)	253	0	0
Proceeds from disposition of operations (Note 4)	0	0	403
Proceeds from sale of nonstrategic assets	6	4	26
Proceeds from sale of nonstrategic timberlands (Notes 4 and 8)	297	0	203
Proceeds from redemption of ownership in related party (Note 8)	0	0	108
Other	15	(17)	46
Net cash from investing activities	187	(440)	367
Cash flows from financing activities:
Cash dividends on common shares	(1,013)	(995)	(941)
Proceeds from issuance of long-term debt (Note 12)	739	0	225
Payments on long-term debt (Note 12)	(512)	(62)	(831)
Proceeds from borrowings on line of credit (Note 11)	1,095	425	100
Payments on line of credit (Note 11)	(1,290)	0	(100)
Payments on debt held by variable interest entities (Note 8)	(302)	(209)	0
Proceeds from exercise of stock options	13	52	128
Repurchases of common shares (Note 15)	(60)	(366)	0
Other	(18)	(7)	(1)
Net cash from financing activities	(1,348)	(1,162)	(1,420)
Net change in cash and cash equivalents	(195)	(490)	148
Cash and cash equivalents at beginning of year	334	824	676
Cash and cash equivalents at end of year	139	334	824
Cash paid (received) during the year for:
Interest, net of amounts capitalized of $5 in 2019, $9 in 2018 and $9 in 2017	370	358	381
Income taxes, net of refunds	$ (2)	$ 95	$ 169

CONSOLIDATED STATEMENT OF CAS_2

CONSOLIDATED STATEMENT OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Cash Flows [Abstract]
Interest, amount capitalized	$ 5	$ 9	$ 9

CONSOLIDATED STATEMENT OF CHANG

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common shares:	Other capital:	Retained earnings (accumulated deficit):	Accumulated other comprehensive loss:
Balance at beginning of year at Dec. 31, 2016		$ 936	$ 8,282	$ 1,421	$ (1,459)
Issued for exercise of stock options and vested restricted stock units		8	128
Repurchases of common shares (Note 15)		0	0
Share-based compensation			35
Other transactions, net			(6)
Net earnings (loss)	$ 582			582
Dividends on common shares				(944)
Adjustments related to new accounting pronouncements (Note 1)				19
Other comprehensive income					(103)
Adjustments related to new accounting pronouncements and other (Note 15)					0
Balance at end of year at Dec. 31, 2017	$ 8,899	944	8,439	1,078	(1,562)
Dividends paid per common share	$ 1.25
Issued for exercise of stock options and vested restricted stock units		4	49
Repurchases of common shares (Note 15)		(15)	(351)
Share-based compensation			42
Other transactions, net			(7)
Net earnings (loss)	$ 748			748
Dividends on common shares				(995)
Adjustments related to new accounting pronouncements (Note 1)				262
Other comprehensive income					672
Adjustments related to new accounting pronouncements and other (Note 15)					(262)
Balance at end of year at Dec. 31, 2018	$ 9,046	933	8,172	1,093	(1,152)
Dividends paid per common share	$ 1.32
Issued for exercise of stock options and vested restricted stock units		2	12
Repurchases of common shares (Note 15)		(3)	(57)
Share-based compensation			30
Other transactions, net			(5)
Net earnings (loss)	$ (76)			(76)
Dividends on common shares				(1,013)
Adjustments related to new accounting pronouncements (Note 1)				(7)
Other comprehensive income					248
Adjustments related to new accounting pronouncements and other (Note 15)					0
Balance at end of year at Dec. 31, 2019	$ 8,177	$ 932	$ 8,152	$ (3)	$ (904)
Dividends paid per common share	$ 1.36

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	NOTES TO CONSOLIDATED FINANCIAL STATEMENTS NOTE 1: SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Our significant accounting policies describe: • our election to be taxed as a real estate investment trust, • how we report our results, • changes in how we report our results and • how we account for various items. OUR ELECTION TO BE TAXED AS A REAL ESTATE INVESTMENT TRUST (REIT) Starting with our 2010 fiscal year, we elected to be taxed as a REIT. REIT income can be distributed to shareholders without first paying corporate level tax, substantially eliminating the double taxation on income. We expect to derive most of our REIT income from investments in timberlands, including the sale of standing timber through pay-as-cut sales contracts and lump sum timber deeds. We have not been subject to REIT built-in gains tax since December 31, 2014. We continue to be required to pay federal corporate income taxes on earnings of our Taxable REIT Subsidiaries ( HOW WE REPORT OUR RESULTS Our report includes: • consolidated financial statements, • our business segments, • estimates, • fair value measurements and • foreign currency translation. Consolidated Financial Statements Our consolidated financial statements provide an overall view of our results and financial condition. They include our accounts and the accounts of entities that we control, including: • majority-owned domestic and foreign subsidiaries and • variable interest entities in which we are the primary beneficiary. They do not include our intercompany transactions and accounts, which are eliminated. Throughout these Notes to Consolidated Financial Statements , unless specified otherwise, references to “Weyerhaeuser,” "the company," “we” and “our” refer to the consolidated company. Our Business Segments Reportable business segments are determined based on the company’s "management approach," as defined by Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 280, Segment Reporting We are principally engaged in: • growing and harvesting timber; • manufacturing, distributing and selling products made from trees; • maximizing the value of every acre we own through the sale of higher and better use (HBU) properties and • monetizing the value of surface and subsurface assets through leases and royalties. Our business segments are organized based primarily on products and services. SEGMENT PRODUCTS AND SERVICES Timberlands Logs, timber, recreational leases and other products Real Estate & ENR Real Estate (sales of timberlands) and ENR (rights to explore for and extract hard minerals, construction materials, oil and gas production, wind and solar) Wood Products Structural lumber, oriented strand board, engineered wood products and building materials distribution We also transfer raw materials, semi-finished materials and end products among our business segments. Because of this intracompany activity, accounting for our business segments involves pricing products transferred between our business segments at current market values. Unallocated Items are gains or charges related to company level initiatives or previous businesses that are not allocated to our current business segments. They include all or a portion of items such as share-based compensation, pension and postretirement costs, elimination of intersegment profit in inventory and LIFO , foreign exchange transaction gains and losses , interest income and other as well as legacy obligations such as environmental remediation and workers compensation. Estimates We prepare our financial statements according to U.S. generally accepted accounting principles (U.S. GAAP). This requires us to make estimates and assumptions during our reporting periods and at the date of our financial statements. The estimates and assumptions affect our: • reported amounts of assets, liabilities and equity; • disclosure of contingent assets and liabilities and • reported amounts of revenues and expenses. While we do our best in preparing these estimates, actual results can and do differ from those estimates and assumptions. Fair Value Measurements We use a fair value hierarchy in accounting for certain nonfinancial assets and liabilities including: • long-lived assets (asset groups) measured at fair value for an impairment assessment; • pension plan assets measured at fair value and • asset retirement obligations initially measured at fair value. The fair value hierarchy is based on inputs to valuation techniques that are used to measure fair value that are either observable or unobservable. Observable inputs reflect assumptions market participants would use in pricing an asset or liability based on market data obtained from independent sources while unobservable inputs reflect a reporting entity’s pricing based upon its own market assumptions. The fair value hierarchy consists of the following three levels: • Level 1: Inputs are unadjusted quoted prices for identical assets or liabilities traded in an active market. • Level 2: Inputs are quoted prices in non-active markets for which pricing inputs are observable either directly or indirectly at the reporting date. • Level 3: Inputs are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable. Foreign Currency Translation We translate foreign currencies into U.S. dollars in two ways: • assets and liabilities — at the exchange rates in effect as of our balance sheet date and • revenues and expenses — at average monthly exchange rates throughout the year. CHANGES IN HOW WE REPORT OUR RESULTS Changes in how we report our results come from: • reclassification of certain balances and results from prior years to make them consistent with our current reporting and • accounting changes made upon our adoption of new accounting guidance. Reclassifications We have reclassified certain balances and results from prior years to be consistent with our 2019 reporting. This makes year-to-year comparisons easier. Our reclassifications had no effect on consolidated net earnings or equity. New Accounting Pronouncements Lease Recognition On January 1, 2019 we adopted FASB ASC Topic 842, Leases With this adoption approach, financial information was not updated and disclosures required under the new standard were not provided for dates and periods before January 1, 2019. The adoption resulted in the recognition of additional right-of-use assets and lease liabilities for leases that each constitute less than 2 percent of total assets on our Consolidated Balance Sheet . These leases are primarily related to vehicles, equipment, office and warehouse locations as disclosed in Note 17: Leases . Benefit Plans Disclosure In August 2018, the FASB issued ASU 2018-14, which requires certain new disclosures, such as an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period, as well as removes the requirement to disclose certain previously required information. The new guidance is effective retrospectively for all periods presented for fiscal periods starting after December 15, 2020, and early adoption is permitted. We adopted this ASU on December 31, 2019 and have updated our disclosures accordingly. This pronouncement does not have an effect on our consolidated financial statements. Refer to Note 9: Pension and Other Postretirement Benefit Plans HOW WE ACCOUNT FOR VARIOUS ITEMS This section provides information about how we account for certain key items related to: • capital investments, • financing our business and • operations. ITEMS RELATED TO CAPITAL INVESTMENTS Key items related to accounting for capital investments pertain to property and equipment, timber and timberlands and impairment of long-lived assets. Property and Equipment We maintain property accounts on an individual asset basis and account for them as follows: • Improvements to and replacements of major units of property are capitalized. • Maintenance, repairs and minor replacements are expensed. • Depreciation is calculated using a straight-line method at rates based on estimated service lives. • Costs associated with logging roads that we intend to utilize for a period longer than one year are capitalized. These roads are then amortized over an estimated service life. • Cost and accumulated depreciation of property sold or retired are removed from the accounts and the gain or loss is included in earnings. Timber and Timberlands We carry timber and timberlands at cost less depletion. Depletion refers to the carrying value of timber that is harvested, lost as a result of casualty or sold. Key activities affecting how we account for timber and timberlands include: • reforestation, • depletion and • forest management in Canada. Reforestation. Generally, we capitalize initial site preparation and planting costs as reforestation and then expense costs after the first planting as they are incurred or over the period of expected benefit. These expensed costs include: • fertilization, • vegetation and insect control, • pruning and precommercial thinning and • property taxes. Accounting practices for these costs do not change when timber becomes merchantable and harvesting starts. Timber depletion. To determine depletion rates, we divide the net carrying value of timber by the related volume of timber estimated to be available over the growth cycle. To determine the growth cycle volume of timber, we consider: • regulatory and environmental constraints, • our management strategies, • inventory data improvements, • growth rate revisions and recalibrations and • known dispositions and inoperable acres. In addition, the duration of the harvest cycle varies by geographic region and species of timber. Depletion rate calculations do not include estimates for: • future silviculture or sustainable forest management costs associated with existing stands; • future reforestation costs associated with a stand's final harvest and • future volume in connection with the replanting of a stand subsequent to its final harvest. We include the cost of timber harvested in the carrying values of raw materials and product inventories. As these inventories are sold to third parties, we include them in costs of sales. Forest Management in Canada. We manage timberlands under long-term licenses in various Canadian provinces that are: • granted by the provincial governments; • granted for initial periods of 15 to 25 years and • renewable provided we meet reforestation, operating and management guidelines. Calculation of the fees we pay on the timber we harvest: • varies from province to province, • is tied to product market pricing and • depends upon the allocation of land management responsibilities in the license. Impairment of Long-Lived Assets We review the carrying value of long-lived assets whenever an event or a change in circumstance indicates that the carrying value of the asset or asset group may not be recoverable through future operations. The carrying value is the original cost, less accumulated depreciation and any past impairments recorded. Impaired assets held for use are written down to fair value. Impaired assets held for sale are written down to fair value less cost to sell. We determine fair value based on: • appraisals, • market pricing of comparable assets, • discounted value of estimated future cash flows from the asset, • replacement values of comparable assets and • agreed upon sale price or offer price. ITEMS RELATED TO FINANCING OUR BUSINESS Key items related to financing our business include financial instruments, cash and cash equivalents, accounts payable and concentration of risk. Financial Instruments We estimate the fair value of financial instruments where appropriate. The assumptions we use — including the discount rate and estimates of cash flows — can significantly affect our fair-value amounts. Our fair values are estimates and may not match the amounts we would realize upon sale or settlement of our financial positions. Cash Equivalents Cash equivalents are investments with maturities of 90 days or less at the date of purchase. We state cash equivalents at cost, which approximates market. Accounts Payable Our banking system replenishes our major bank accounts daily as checks we have issued are presented for payment. As a result, we may have negative book cash balances due to outstanding checks that have not yet been paid by the bank. These negative balances would be included in "Accounts payable" on our Consolidated Balance Sheet . Changes in these negative cash balances would be reported as financing activities on our Consolidated Statement of Cash Flows . We had no negative book cash balances as of December 31, 2019 or December 31, 2018 Concentration of Risk We disclose customers that represent a concentration of risk. As of December 31, 2019, and December 31, 2018, no customer accounted for 10 percent or more of our net sales. ITEMS RELATED TO OPERATIONS Key items related to operations include revenue recognition, inventories, shipping and handling costs, income taxes, pension and other postretirement benefit plans and environmental remediation. Revenue Recognition Refer to Note 3: Revenue Recognition for detail on how we account for revenue. Inventories We state inventories at the lower of cost or net realizable value. Cost includes labor, materials and production overhead. LIFO — the last-in, first-out method — applies to major inventory products held at our U.S. domestic locations. We began to use the LIFO method for domestic products in the 1940s as required to conform with the tax method elected. Subsequent acquisitions of entities added new products under the FIFO — the first-in, first-out method — or moving average cost methods that have continued under those methods. The FIFO or moving average cost method applies to the balance of our domestic raw material and product inventories as well as for all material and supply inventories and all foreign inventories. Shipping and Handling Costs We classify shipping and handling costs in "Costs of sales" on our Consolidated Statement of Operations . Income Taxes We account for income taxes under the asset and liability method. Unrecognized tax benefits represent potential future funding obligations to taxing authorities if uncertain tax positions we have taken on previously filed tax returns are not sustained. Accrued interest and penalties related to unrecognized tax benefits are recognized as a component of income tax expense. We recognize deferred tax assets and liabilities to reflect: • future tax consequences due to differences between the carrying amounts for financial reporting purposes and the tax bases of certain items and • net operating loss and tax credit carryforwards. To measure deferred tax assets and liabilities, we: • determine when the differences between the carrying amounts and tax bases of affected items are expected to be recovered or resolved and • use enacted tax rates expected to apply to taxable income in those years. Pension and Other Postretirement Benefit Plans We recognize the overfunded or underfunded status of our defined benefit pension and other postretirement plans on our Consolidated Balance Sheet and recognize changes in the funded status through comprehensive income (loss) in the year in which the changes occur. Actuarial valuations determine the amount of the pension and other postretirement benefit obligations and the net periodic benefit cost we recognize. The net periodic benefit cost includes: • cost of benefits provided in exchange for employees’ services rendered during the year; • interest cost of the obligations; • expected long-term return on plan assets; • gains or losses on plan settlements and curtailments; • amortization of prior service costs and plan amendments over the average remaining service period of the active employee group covered by the plans or the average remaining life expectancy in situations where the plan participants affected by the plan amendment are inactive and • amortization of cumulative unrecognized net actuarial gains and losses — generally in excess of 10 percent of the greater of the benefit obligation or the combination of market-related and fair value of plan assets at the beginning of the year — over the average remaining service period of the active employee group covered by the plans or the average remaining life expectancy in situations where the plan participants are inactive. Pension plans. We have defined benefit pension plans covering approximately half of our employees. Determination of benefits differs for salaried, hourly and union employees as follows: • Salaried employee benefits are based on each employee’s highest monthly earnings for five consecutive years during the final 10 years before retirement. • Hourly and union employee benefits generally are stated amounts for each year of service. • Union employee benefits are set through collective-bargaining agreements. We contribute to our U.S. and Canadian pension plans according to established funding standards. The funding standards for the plans are: • U.S. pension plans — according to the Employee Retirement Income Security Act of 1974 and • Canadian pension plans — according to the applicable provincial pension act and the Income Tax Act. Postretirement benefits other than pensions. We provide certain postretirement health care and life insurance benefits for some retired employees. In some cases, we pay a portion of the cost of the benefit. Note 9: Pension and Other Postretirement Benefit Plans provides additional information about our postretirement benefit plans. Environmental Remediation We accrue losses associated with environmental remediation obligations when such losses are probable and reasonably estimable. Future expenditures for environmental remediation obligations are not discounted to their present value. Recoveries of environmental remediation costs from other parties are recorded as assets when the recovery is deemed probable and does not exceed the amount of losses previously recorded.

BUSINESS SEGMENTS

BUSINESS SEGMENTS	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
BUSINESS SEGMENTS	NOTE 2: BUSINESS SEGMENTS Our business segments and how we account for those segments are discussed in Note 1: Summary of Significant Accounting Policies . This note provides key financial data by business segment. KEY FINANCIAL DATA BY BUSINESS SEGMENT Sales and Net Contribution (Charge) to Earnings DOLLAR AMOUNTS IN MILLIONS TIMBERLANDS REAL ESTATE & ENR WOOD PRODUCTS UNALLOCATED ITEMS AND INTERSEGMENT ELIMINATIONS CONSOLIDATED Sales to unaffiliated customers (1) 2019 $ 1,618 $ 313 $ 4,623 $ — $ 6,554 2018 $ 1,873 $ 306 $ 5,297 $ — $ 7,476 2017 $ 1,893 $ 280 $ 5,023 $ — $ 7,196 Intersegment sales (1) 2019 $ 503 $ 1 $ — $ (504 ) $ — 2018 $ 537 $ 1 $ — $ (538 ) $ — 2017 $ 522 $ 1 $ — $ (523 ) $ — Net contribution (charge) to earnings 2019 $ 347 $ 144 $ 353 $ (679 ) $ 165 2018 $ 583 $ 127 $ 838 $ (366 ) $ 1,182 2017 $ 532 $ 146 $ 569 $ (138 ) $ 1,109 (1) In 2019, we changed the way we report our Canadian Forestlands operations. As a result, we no longer report related intersegment sales in the Timberlands segment and we now record the minimal associated third-party log sales in the Wood Products segment. These collective transactions did not contribute any earnings to the Timberlands or Wood Products segment. We have conformed prior year presentations with the current year. Management evaluates segment performance based on the net contribution (charge) to earnings of the respective segments. An analysis and reconciliation of our business segment information to the consolidated financial statements follows: Reconciliation of Net Contribution to Earnings to Net Earnings (Loss) DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Net contribution to earnings $ 165 $ 1,182 $ 1,109 Interest expense, net of capitalized interest (378 ) (375 ) (393 ) Income (loss) before income taxes (213 ) 807 716 Income taxes 137 (59 ) (134 ) Net earnings (loss) $ (76 ) $ 748 $ 582 Additional Financial Information DOLLAR AMOUNTS IN MILLIONS TIMBERLANDS REAL ESTATE & ENR WOOD PRODUCTS UNALLOCATED ITEMS CONSOLIDATED Depreciation, depletion and amortization 2019 $ 301 $ 14 $ 191 $ 4 $ 510 2018 $ 319 $ 14 $ 149 $ 4 $ 486 2017 $ 356 $ 15 $ 145 $ 5 $ 521 Capital expenditures 2019 $ 112 $ — $ 257 $ 15 $ 384 2018 $ 117 $ — $ 306 $ 4 $ 427 2017 $ 115 $ 2 $ 299 $ 3 $ 419 Total Assets DOLLAR AMOUNTS IN MILLIONS TIMBERLANDS and REAL ESTATE & ENR WOOD PRODUCTS UNALLOCATED ITEMS CONSOLIDATED Total assets (1)(2) 2019 $ 13,130 $ 2,452 $ 824 $ 16,406 2018 $ 13,792 $ 2,280 $ 1,177 $ 17,249 (1) In 2019, we changed the way we report our Canadian Forestlands operations. As a result, Canadian Forestlands assets previously reported in the Timberlands segment are now recorded in the Wood Products segment. We have conformed prior year presentations with the current year. (2) Assets attributable to the Real Estate & ENR business segment are combined with total assets for the Timberlands segment as we do not produce separate balance sheets internally.

REVENUE RECOGNITION

REVENUE RECOGNITION	12 Months Ended
	Dec. 31, 2019
Revenue From Contract With Customer [Abstract]
REVENUE RECOGNITION	NOTE 3: REVENUE RECOGNITION A majority of our revenue is derived from sales of delivered logs and manufactured wood products. We account for revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers Consolidated Statement of Operations , Consolidated Balance Sheet or Consolidated Statement of Cash Flows . PERFORMANCE OBLIGATIONS A performance obligation, as defined in ASC Topic 606, is a promise in a contract to transfer a distinct good or service to a customer. A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue at the point in time, or over the period, in which the performance obligation is satisfied. Performance obligations associated with delivered log sales are typically satisfied when the logs are delivered to our customers’ mills or delivered to an ocean vessel in the case of export sales. Performance obligations associated with the sale of wood products are typically satisfied when the products are shipped. We have elected, as an accounting policy, to treat shipping and handling that is performed after a customer obtains control of the product as an activity required to fulfill the promise to transfer the good; therefore we will not evaluate this requirement as a separate performance obligation. Customers are generally invoiced shortly after logs are delivered or after wood products are shipped, with payment generally due within a month or less of the invoice date. ASC Topic 606 requires entities to consider significant financing components of contracts with customers, though allows for the use of a practical expedient when the period between satisfaction of a performance obligation and payment receipt is one year or less. Given the nature of our revenue transactions, we have elected to utilize this practical expedient. Performance obligations associated with real estate sales are generally met when placed into escrow and all conditions of closing have been satisfied. CONTRACT ESTIMATES Substantially all of our performance obligations are satisfied as of a point in time. Therefore, there is little judgment in determining when control transfers for our business segments as described above. The transaction price for log sales generally equals the amount billed to our customer for logs delivered during the accounting period. For the limited number of log sales subject to a long-term supply agreement, the transaction price is variable but is known at the time of billing. For wood products sales, the transaction price is generally the amount billed to the customer for the products shipped but may be reduced slightly for estimated cash discounts and rebates. There are no significant contract estimates related to the real estate business. CONTRACT BALANCES In general, customers are billed and a receivable is recorded as we ship and/or deliver wood products and logs. We generally receive payment shortly after products have been received by our customers. Contract asset and liability balances are immaterial. For real estate sales, the company receives the entire consideration in cash at closing. MAJOR PRODUCTS A Reconciliation of Revenue Recognized by our Major Products: DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Net sales to unaffiliated customers: Timberlands segment (1) Delivered logs: West Domestic sales $ 375 $ 503 $ 473 Export grade sales 365 484 442 Subtotal West 740 987 915 South 640 625 616 North (2) 92 99 95 Other (3) — — 23 Subtotal delivered logs sales 1,472 1,711 1,649 Stumpage and pay-as-cut timber 42 59 73 Recreational and other lease revenue 61 59 59 Other (4) 43 44 112 Net sales attributable to Timberlands segment 1,618 1,873 1,893 Real Estate & ENR segment Real estate 225 229 208 Energy and natural resources 88 77 72 Net sales attributable to Real Estate & ENR segment 313 306 280 Wood Products segment (1) Structural lumber 1,892 2,258 2,058 Oriented strand board 632 891 904 Engineered solid section 510 521 500 Engineered I-joists 323 336 336 Softwood plywood 161 200 176 Medium density fiberboard 166 177 183 Complementary building products 602 584 541 Other (5) 337 330 325 Net sales attributable to Wood Products segment 4,623 5,297 5,023 Total $ 6,554 $ 7,476 $ 7,196 (1 ) In 2019, we changed the way we report our Canadian Forestlands operations. As a result, we no longer report related intersegment sales in the Timberlands segment and we now record the minimal associated third-party log sales in the Wood Products segment. These collective transactions did not contribute any earnings to the Timberlands or Wood Products segment. We have conformed prior year presentations with the current year. (2) In November 2019, we sold our Michigan timberlands. Refer to Note 4: Divestitures and Assets Held for Sale for further information on this divestiture. (3) Other delivered logs included sales from timberlands managed for the Twin Creeks Venture. Our management agreement for the Twin Creeks Venture began in April 2016 and terminated in December 2017. For additional information see Note 8: Related Parties . ( 4 ) Other Timberlands sales includes sales of seeds and seedlings from our nursery operations as well as wood chips. Prior to our Uruguay operations being divested in September 2017, sales from these operations were included within this amount as well. Refer to Note 4: Divestitures and Assets Held for Sale for further information on this divestiture. ( 5 ) Other Wood Products sales include wood chips, other byproducts and third-party residual log sales from our Canadian Forestlands operations.

DIVESTITURES AND ASSETS HELD FO

DIVESTITURES AND ASSETS HELD FOR SALE	12 Months Ended
	Dec. 31, 2019
Discontinued Operations And Disposal Groups [Abstract]
DIVESTITURES AND ASSETS HELD FOR SALE	NOTE 4: DIVESTITURES AND ASSETS HELD FOR SALE DIVESTITURES On September 16, 2019, we announced an agreement to sell 555,000 acres of Michigan timberlands, which was part of our Timberlands business segment. On November 13, 2019, we completed the sale to an affiliate of The Lyme Timber Company LP for $297 million of cash proceeds, which is net of purchase price adjustments and closing costs. As a result of the sale, we recorded a $48 million gain in the Timberlands segment. On September 1, 2017, we completed the sale of our Uruguay timberlands and manufacturing operations to a consortium led by BTG Pactual's Timberland Investment Group, including other long-term investors, for $403 million of cash proceeds. Due to the impairment of our Uruguay operations recorded during second quarter 2017 (refer to Note 18: Charges for Integration and Restructuring, Closures and Asset Impairments ), no material gain or loss was recorded as a result of this sale. Neither of the divestitures discussed above were considered strategic shifts that had or will have a major effect on our operations or financial results and therefore did not meet the requirements for presentation as discontinued operations. ASSETS HELD FOR SALE On December 17, 2019, we announced an agreement to sell 630,000 acres of Montana timberlands for $145 million in cash, which is subject to customary closing conditions. This sale to Southern Pine Plantations is expected to close in second quarter 2020, and the transaction relates to the Timberlands segment. The sale of our Montana timberlands is not considered a strategic shift that has, or will have, a major effect on our operations or financial results and therefore does not meet the requirements for presentation as discontinued operations. However, the related assets have met the relevant criteria to be classified as held for sale in the current period Consolidated Balance Sheet Note 18: Charges for Integration and Restructuring, Closures and Asset Impairments Consolidated Statement of Operations Consolidated Balance Sheet As of December 31, 2019, “Assets held for sale” had a balance of $140 million, which consisted primarily of timberlands and other related assets, after an impairment of $80 million.

NET EARNINGS (LOSS) PER SHARE

NET EARNINGS (LOSS) PER SHARE	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
NET EARNINGS (LOSS) PER SHARE	NOTE 5: NET EARNINGS (LOSS) PER SHARE Our basic and diluted earnings (loss) per share for the last three years were: • $(0.10) • $0.99 • $0.77 HOW WE CALCULATE BASIC AND DILUTED NET EARNINGS (LOSS) PER SHARE Basic earnings (loss) per share is net earnings (loss) available to common shareholders divided by the weighted average number of our outstanding common shares, including stock equivalent units where there is no circumstance under which those shares would not be issued. Diluted earnings (loss) per share is net earnings (loss) available to common shareholders divided by the sum of the: • weighted average number of our outstanding common shares and • the effect of our outstanding dilutive potential common shares. Dilutive potential common shares may include: • outstanding stock options, • restricted stock units and • performance share units. Calculation of Weighted Average Number of Outstanding Common Shares – Dilutive SHARES IN THOUSANDS 2019 2018 2017 Weighted average number of outstanding shares - basic 745,897 754,556 753,085 Dilutive potential common shares: Stock options — 1,310 2,571 Restricted stock units — 566 582 Performance share units — 395 428 Total effect of outstanding dilutive potential common shares — 2,271 3,581 Weighted average number of outstanding common shares - dilutive 745,897 756,827 756,666 We use the treasury stock method to calculate the dilutive effect of our outstanding stock options, restricted stock units and performance share units. Share-based payment awards that are contingently issuable upon the achievement of specified performance or market conditions are included in our diluted earnings per share calculation in the period in which the conditions are satisfied. SHARES EXCLUDED FROM DILUTIVE EFFECT The following shares were not included in the computation of diluted earnings (loss) per share because they were either antidilutive or the required performance or market conditions were not met. Some or all of these shares may be dilutive potential common shares in future periods. Potential Shares Not Included in the Computation of Diluted Earnings (Loss) per Share SHARES IN THOUSANDS 2019 2018 2017 Stock options 2,631 2,402 1,351 Restricted stock units 477 — — Performance share units 1,131 1,080 799

INVENTORIES

INVENTORIES	12 Months Ended
	Dec. 31, 2019
Inventory Disclosure [Abstract]
INVENTORIES	NOTE 6: INVENTORIES Inventories include raw materials, work-in-process, finished goods as well as materials and supplies, as shown below: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 LIFO inventories: Logs $ 19 $ 11 Lumber, plywood, panels and fiberboard 82 75 Other products 10 10 FIFO or moving average cost inventories: Logs 28 35 Lumber, plywood, panels, fiberboard and engineered wood products 84 86 Other products 98 83 Materials and supplies 95 89 Total $ 416 $ 389 If we used FIFO for all LIFO inventories, our stated inventories would have been higher by $76 million as of December 31, 2019 December 31, 2018 HOW WE ACCOUNT FOR OUR INVENTORIES The Inventories section of Note 1: Summary of Significant Accounting Policies provides details about how we account for our inventories.

PROPERTY AND EQUIPMENT

PROPERTY AND EQUIPMENT	12 Months Ended
	Dec. 31, 2019
Property Plant And Equipment [Abstract]
PROPERTY AND EQUIPMENT	NOTE 7: PROPERTY AND EQUIPMENT Property and equipment includes land, buildings and improvements, machinery and equipment, roads and other items. Carrying Value of Property and Equipment and Estimated Service Lives DOLLAR AMOUNTS IN MILLIONS RANGE OF LIVES DECEMBER 31, 2019 DECEMBER 31, 2018 Property and equipment, at cost: Land N/A $ 87 $ 87 Buildings and improvements 15-40 999 942 Machinery and equipment 5-25 3,425 3,240 Roads 10-35 742 785 Other 3-10 193 179 Total cost 5,446 5,233 Accumulated depreciation and amortization (3,477 ) (3,376 ) Property and equipment, net $ 1,969 $ 1,857 SERVICE LIVES AND DEPRECIATION In general, additions are classified into components, each with its own estimated useful life as determined at the time of purchase. Depreciation and amortization expense for property and equipment was: • $240 million • $197 million • $206 million in 2017.

RELATED PARTIES

RELATED PARTIES	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
RELATED PARTIES	NOTE 8: RELATED PARTIES This note provides details about our transactions with related parties. For the years presented, our material related parties have consisted of: • variable interest entities and • our Twin Creeks Venture. VARIABLE INTEREST ENTITIES From 2002 through 2004, we sold certain nonstrategic timberlands. As a result of these sales, buyer-sponsored and monetization variable interest entities, or special purpose entities (SPEs), were formed. We are the primary beneficiary and consolidate the assets and liabilities of the SPEs involved in these transactions. The assets of the buyer-sponsored SPEs are financial investments which consist of bank guarantees. These bank guarantees are in turn backed by bank notes, which are the liabilities of the monetization SPEs. Interest earned from the financial investments within the buyer-sponsored SPEs is used to pay interest accrued on the corresponding monetization SPE’s note. We have an equity interest in the monetization SPEs, but no ownership interest in the buyer-sponsored SPEs. The following disclosures refer to assets of buyer-sponsored SPEs and liabilities of monetization SPEs. However, because these SPEs are distinct legal entities: • Assets of the SPEs are not available to satisfy our liabilities or obligations. • Liabilities of the SPEs are not our liabilities or obligations. During first quarter 2019, we received a $253 million payment from a buyer-sponsored SPE. As of December 31, 2019, we had an asset totaling $362 million related to one buyer-sponsored SPE remaining on our Consolidated Balance Sheet . We paid $302 million and $209 million related to liabilities from our monetized SPEs in third quarter 2019 and fourth quarter 2018, respectively. These payments were made upon maturity and there are no further obligations remaining. Our Consolidated Statement of Operations includes: • Interest income on buyer-sponsored SPE investments of – $22 million in 2019, – $34 million in 2018 and – $34 million in 2017. • Interest expense on monetization SPE notes of – $12 million in 2019, – $29 million in 2018 and – $29 million in 2017. The weighted average interest rate on our buyer-sponsored SPEs was 5.5 percent during 2019 and 2018. The interest rate on the monetization SPE that matured in 2019 and the weighted average interest rate on our monetization SPEs during 2018 was 5.6 percent. TWIN CREEKS VENTURE Ownership Redemption, Agreement Termination and Sale Recognition During October 2017, we redeemed our 21 percent ownership interest in the Twin Creeks Venture for $108 million in cash. We did not recognize a material gain or loss on the redemption of our ownership interest. The cash received was classified as a cash flow from investing activities on our Consolidated Statement of Cash Flows . Effective December 31, 2017, we terminated the agreements under which we had managed the Twin Creeks timberlands. Following termination of these agreements, Weyerhaeuser has no further responsibilities or obligations related to the Twin Creeks Venture and our continuing involvement in the contributed timberlands ceased. In fourth quarter 2017, we recognized the sale of the original contribution of timberlands that occurred in April 2016. Sale of Additional Timberlands to Twin Creeks In conjunction with the redemption and termination discussed above, we also entered an agreement to sell 100,000 acres of Southern timberlands to Twin Creeks for $203 million. The sale, which included 80,000 acres of timberlands in Mississippi and 20,000 acres in Georgia, closed December 29, 2017. The sale resulted in a $99 million gain recognized during fourth quarter 2017.

PENSION AND OTHER POSTRETIREMEN

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS	12 Months Ended
	Dec. 31, 2019
Pension And Other Postretirement Benefit Expense [Abstract]
PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS	NOTE 9: PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS This note provides details about defined benefit and defined contribution plans we sponsor for our employees. The "Pension and Other Postretirement Benefit Plans" section of Note 1: Summary of Significant Accounting Policies DEFINED BENEFIT PLANS WE SPONSOR OVERVIEW OF PLANS The defined benefit pension plans we sponsor in the U.S. and Canada differ according to each country’s requirements. In the U.S., we have plans that qualify under the Internal Revenue Code (qualified plans), as well as plans for select employees that provide additional benefits not qualified under the Internal Revenue Code (nonqualified plans). In Canada, we have plans that are registered under the Income Tax Act and applicable provincial pension acts (registered plans), as well as nonregistered plans for select employees that provide additional benefits that may not be registered under the Income Tax Act or provincial pension acts (nonregistered plans). We also offer other postretirement benefit plans in the U.S. and Canada , Actions to Reduce Pension Plan Obligations As a part of our continued efforts to reduce pension plan obligations, we transferred approximately $1.5 billion of U.S. qualified pension plan assets and liabilities to an insurance company through the purchase of a group annuity contract in January 2019 (2019 Retiree Annuity Purchase). In connection with this transaction, we recorded a preliminary noncash pretax settlement charge of $455 million during first quarter 2019, accelerating the recognition of previously unrecognized losses in “Accumulated other comprehensive loss”, that would have been recognized in subsequent periods. In second quarter 2019, we finalized the prior year-end fair value of pension plan assets and obligations, which reduced the settlement charge by $6 million for a final settlement charge of $449 million. This settlement triggered a remeasurement of plan assets and liabilities. We updated the discount rate used to measure our projected benefit obligation for the U.S. qualified pension plan as of January 31, 2019, as well as our discount rate used to calculate the related net periodic benefit cost for the remainder of 2019 to 4.30 percent from 4.40 percent. All other assumptions remained unchanged. The net effect of the remeasurement was a $24 million reduction in funded status, primarily driven by the decrease in discount rate. This change in funded status was reflected in our first quarter 2019 Consolidated Balance Sheet . Additionally, we settled the assets and liabilities associated with three Canadian registered pension plans through the purchase of a group annuity contract in October 2019. As a result of the transaction, we recorded a noncash pretax settlement charge of $6 million. During 2018, we offered select U.S. terminated vested plan participants the opportunity to elect an immediate lump sum distribution. Lump sum distributions were paid from plan assets totaling $664 million during fourth quarter 2018. We recorded a settlement charge of $200 million during fourth quarter 2018 related to this transaction. The settlement triggered a plan remeasurement, however due to the short period between the settlement and our normal year-end remeasurement, the effect on net periodic benefit cost was insignificant. To maintain the U.S. qualified pension plan's funded status in connection with these transactions, we contributed $300 million to the plan during third quarter 2018. Refer to Note 21: Income Taxes for details on the tax effects of this transaction. FUNDED STATUS OF PLANS The funded status of the plans we sponsor is determined by comparing the projected benefit obligation with the fair value of plan assets at the end of the year. The following table demonstrates how our plans' funded status is reflected on the Consolidated Balance Sheet . DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2019 2018 Funded status: Fair value of plan assets (1) $ 3,719 $ 4,930 $ 19 $ 18 Projected benefit obligations (4,260 ) (5,263 ) (151 ) (166 ) Funded status (541 ) (333 ) (132 ) (148 ) Presentation on our Consolidated Balance Sheet Noncurrent assets $ 47 $ 74 $ — $ — Current liabilities (19 ) (18 ) (8 ) (10 ) Noncurrent liabilities (569 ) (389 ) (124 ) (138 ) Funded status $ (541 ) $ (333 ) $ (132 ) $ (148 ) (1) Fair value of plan assets as of December 31, 2018 includes amounts associated with the $300 million voluntary contribution made during 2018 in anticipation of our 2018 term-vested lump sum and 2019 retiree annuity purchase transactions. Refer to the “Actions to Reduce Pension Plan Obligations” section for further details of this contribution and the related transactions. Assets and liabilities on the Consolidated Balance Sheet are different from the cumulative income or expense that we have recorded associated with the plans. The differences are actuarial gains and losses and prior service costs and credits that are deferred and amortized into periodic benefit costs in future periods. Unamortized amounts are recorded in "Accumulated Other Comprehensive Loss", which is a component of total equity on our Consolidated Balance Sheet . The "Accumulated Other Comprehensive Loss" section of Note 15: Shareholders’ Interest details changes in these amounts by component. Changes in Fair Value of Plan Assets DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2019 2018 Fair value of plan assets at beginning of year (estimated) $ 4,930 $ 5,514 $ 18 $ — Adjustment for final fair value of plan assets 16 44 — — Actual return on plan assets 449 123 1 — Foreign currency translation 38 (73 ) — — Employer contributions and benefit payments 30 345 15 36 Plan participants’ contributions — — 2 4 Plan transfers 1 1 — — Benefits paid (includes lump sum and annuity transfers) (1,745 ) (1,024 ) (17 ) (22 ) Fair value of plan assets at end of year (estimated) $ 3,719 $ 4,930 $ 19 $ 18 We estimate the fair value of pension plan assets based on the information available during the year-end reporting process. In some cases, primarily with regard to private equity funds, the available information consists of net asset values as of an interim date, plus cash flows and market events between the interim date and the end of the year. We update the year-end estimated fair value of pension plan assets during the first half of the next year to incorporate year-end net asset values received after we have filed our Annual Report on Form 10-K. During second quarter 2019, we recorded an increase in the beginning of year fair value of the pension assets of $16 million, or less than 1 percent. We also updated our census data that is used to estimate our beginning of year projected obligation for our pension plans, which resulted in a projected benefit obligation decrease of $6 million, or less than 1 percent. The net effect of these updates was a $22 million improvement in funded status as of December 31, 2018. This change in funded status was reflected in our second quarter 2019 Consolidated Balance Sheet . See additional details about the changes in the fair value of plan assets in the "Pension Assets" section below. Changes in Projected Benefit Obligations of Our Pension and Other Postretirement Benefit Plans DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2019 2018 Projected benefit obligation beginning of year $ 5,263 $ 6,795 $ 166 $ 200 Service cost 32 37 — — Interest cost 160 236 6 7 Plan participants’ contributions — — 2 4 Actuarial (gains) losses 510 (718 ) (8 ) (18 ) Foreign currency translation 39 (69 ) 2 (5 ) Benefits paid (includes lump sum and annuity transfers) (1,745 ) (1,024 ) (17 ) (22 ) Plan amendments and other — 5 — — Plan transfers 1 1 — — Projected benefit obligation at end of year $ 4,260 $ 5,263 $ 151 $ 166 Generally, the largest changes in our “Actuarial (gains) losses” line within the table above are due to changes in discount rates year over year. See additional details about the actuarial assumptions and changes in the projected benefit obligation in the "Actuarial Assumptions" section below. Projected Benefit Obligations Greater Than Plan Assets As of December 31, 2019, pension plans with projected benefit obligations greater than plan assets had: • $3.4 billion in projected benefit obligations and • assets with a fair value of $2.8 billion. As of December 31, 2018, pension plans with projected benefit obligations greater than plan assets had: • $4.5 billion in projected benefit obligations and • assets with a fair value of $4.1 billion. Accumulated Benefit Obligations Greater Than Plan Assets As of December 31, 2019, pension plans with accumulated benefit obligations greater than plan assets had: • $3.3 billion in accumulated benefit obligations and • assets with a fair value of $2.8 billion. As of December 31, 2018, pension plans with accumulated benefit obligations greater than plan assets had: • $4.4 billion in accumulated benefit obligations and • assets with a fair value of $4.1 billion. The accumulated benefit obligation for all of our defined benefit pension plans was: • $4.2 billion at December 31, 2019 and • $5.2 billion at December 31, 2018. PENSION ASSETS Our Investment Policies and Strategies Our investment policies and strategies guide and direct how the funds are managed for the benefit plans we sponsor. These funds include our: • U.S. Pension Trust — funds our U.S. qualified pension plans; • Canadian Pension Trust — funds our Canadian registered pension plans and • Retirement Compensation Arrangements — fund a portion of our Canadian nonregistered pension plans. U.S. and Canadian Pension Trusts At the end of 2018, we began to shift pension plan assets to an allocation that will more closely match the pension plan liability profile going forward. The former investment strategy included investments in hedge funds, private equity funds, derivative instruments and other investments. These asset classes are now generally in redemption and run-off mode however, given the long-term nature of these investments, they will continue to comprise a material portion of the plan assets for several years. We expect all investments in redemption to be redeemed at amounts materially consistent with their net asset values. As these investments are redeemed or liquidated, cash proceeds available for investment will be invested in accordance with our revised investment strategy. The revised investment strategy target s a percent age allocation to growth assets and a percent age allocation to liability hedging assets based on each plan’s funded status . We expect to increase the allocation to liability hedging assets over time as the funded status of the pension plan improves. As of December 31, 2019, we reached a 50 percent allocation to growth assets and a 50 percent allocation to liability hedging assets in the U.S. qualified plan . Growth assets include investments in global equities, hedge funds, which are generally in redemption, and private equity assets, which are generally in run-off mode. Liability hedging assets include corporate credit and government issued fixed income securities and treasury futures selected to align with the plan liabilities. Cash and short-term investments include highly liquid money market and government securities and are primarily held to fund benefit payments, capital calls, margin requirements or to meet regulatory requirements. Cash at December 31, 2019, includes amounts that will be invested in liability hedging assets such as fixed income investments. Fixed income investments include publicly traded corporate and government issued debt. These bonds have varying maturities, credit quality and sector exposure and are selected to align with the duration of our plan liabilities. Additionally, our fixed income portfolio includes repurchase agreements, which represent short-term borrowings to hedge against interest rate risk. We have an obligation to return the cash related to these borrowings in accordance with the agreements, which are collateralized by our government bonds. Due to the nature of these agreements, the outstanding balance of the borrowing approximates fair value. Public equity investments consist of investments in several publicly traded companies as well as exchange traded funds. Hedge fund and related investments are privately-offered managed pools primarily structured as limited liability entities. General members or partners of these limited liability entities serve as portfolio managers and are thus responsible for the fund’s underlying investment decisions. Underlying investments within these funds may include long and short public and private equities, corporate, mortgage and sovereign debt, options, swaps, forwards and other derivative positions. These funds have varying degrees of leverage, liquidity and redemption provisions. Private equity and related investments are investments in private equity, mezzanine, distressed, co-investments and other structures. Private equity funds generally participate in buyouts and venture capital of limited liability entities through unlisted equity and debt instruments. These funds may also borrow at the underlying entity level. Mezzanine and distressed funds generally invest in the debt of public or private companies with additional participation through warrants or other equity options. Derivative instruments have historically been comprised of swaps, futures, forwards or options. Consistent with our shift in asset strategy, our positions in derivative instruments have been significantly reduced. At December 31, 2019, only a small amount of futures remain in our portfolio. Assets within our qualified and registered pension plans in our U.S. and Canadian pension trusts were invested as follows: DECEMBER 31, 2019 DECEMBER 31, 2018 Cash and short-term investments 3.2% 5.8% Fixed income investments: Corporate 33.9 21.5 Government 25.4 8.6 Repurchase agreements (4.7 ) — Public equity investments 0.1 — Hedge funds and related investments 14.3 36.9 Private equity and related investments 27.7 21.9 Derivative instruments, net 0.3 5.6 Accrued liabilities (0.2 ) (0.3 ) Total 100.0% 100.0% Retirement Compensation Arrangements Retirement compensation arrangements fund a portion of our Canadian nonregistered pension plans. As required by Canadian tax rules, approximately 50 percent of these assets are invested into a noninterest-bearing refundable tax account held by the Canada Revenue Agency. This portion of the portfolio does not earn returns. The remaining portion is invested in a portfolio of equities. Managing Risk Investments and contracts are subject to risks including market price, interest rate, credit, currency and liquidity risks. The following provides an overview of these risks and describes governance processes and actions we take to mitigate these risks on our pension plan asset portfolios. Market price risk is the risk that market fluctuations will adversely affect the value of plan assets. The trusts mitigate market price risk by investing in a diversified portfolio. In addition, we and our investment advisers perform regular monitoring with ongoing qualitative assessments, quantitative assessments, and comprehensive investment and operational due diligence. Interest rate risk exists with respect to both assets and liabilities and is the risk that a change in interest rates will adversely affect the fair value of interest rate securities or liabilities, thereby affecting the overall funded status. With the change in investment strategy to more closely match the plan liabilities, interest rate risk will be reduced. Credit risk is the risk that counterparties’ failure to discharge their obligations could affect cash flows. The trusts have exposure primarily through investments in fixed income securities. This risk is mitigated by investing in a diversified portfolio. We are also exposed to credit risk indirectly through counterparty relationships initiated by underlying managers of investments in limited liability pools. This risk is mitigated through initial due diligence and ongoing monitoring processes. Currency risk arises from holding plan assets denominated in a currency other than the currency in which its liabilities are settled. With the change in investment strategy, currency risk will be mitigated going forward by investing more of the Canadian plan assets in Canadian dollar fixed income investments. Liquidity risk is the risk that the trust will not be able to settle liabilities such as payments to participants, counterparties, and service providers. Private equity and hedge fund investments generally have less liquidity than publicly traded investments. With the change in investment strategy and a larger percentage of the plan assets invested in more liquid instruments such as publicly traded fixed income investments, liquidity risk is greatly reduced. Valuation of Our Plan Assets Pension assets are stated at fair value or net asset value (NAV) as of the reporting date. Fair value is based on the amount that would be received to sell an asset or paid to settle a liability in an orderly transaction between market participants at the reporting date. We do not consider forced or distressed sale scenarios. Instead, we consider both observable and unobservable inputs that reflect assumptions applied by market participants when setting the exit price of an asset or liability in an orderly transaction within the principal market for that asset or liability. We value the pension plan assets based upon the observability of exit pricing inputs and classify pension plan assets based upon the lowest level input that is significant to the fair value measurement of the pension plan assets in their entirety. The fair value hierarchy is: • Level 1: Inputs are unadjusted quoted prices for identical assets or liabilities traded in an active market. • Level 2: Inputs are quoted prices in non-active markets for which pricing inputs are observable either directly or indirectly at the reporting date. • Level 3: Inputs are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable. Investments for which fair value is measured using the NAV per share as a practical expedient are not categorized within the fair value hierarchy. Cash and short-term investments are valued at cost, which approximates market. Fixed income and public equity investments are valued at exit prices quoted in active or non-active markets or based on observable inputs. Hedge funds, private equities, and related fund units are valued based on the NAVs of the funds. These values represent the per-unit price at which new investors are permitted to invest and existing investors are permitted to exit. When NAVs as of the end of the year have not been received, we estimate fair value by adjusting the most recently reported NAVs for market events and cash flows between the interim date and the end of the year. Derivative instruments are valued based upon valuation statements received from each derivative’s counterparty. The net pension plan assets, when categorized in accordance with this fair value hierarchy, are as follows. Investments valued using NAV as a practical expedient are presented to reconcile with total plan assets. DOLLAR AMOUNTS IN MILLIONS 2019 LEVEL 1 LEVEL 2 LEVEL 3 NAV TOTAL Pension trust investments: Cash and short-term investments $ 120 $ — $ — $ — $ 120 Fixed income investments: Corporate — 1,260 — — 1,260 Government — 941 — — 941 Repurchase agreements — (176 ) — — (176 ) Public equity investments 4 — — — 4 Hedge fund and related investments — — 13 518 531 Private equity and related investments — — 86 942 1,028 Derivative instruments — 10 — — 10 Total pension trust investments 124 2,035 99 1,460 3,718 Accrued liabilities, net (9 ) Pension trust net assets 3,709 Canadian nonregistered plan assets: Cash and short-term investments 5 — — — 5 Public equity investments 5 — — — 5 Total Canadian nonregistered plan assets 10 — — — 10 Total plan assets $ 3,719 DOLLAR AMOUNTS IN MILLIONS 2018 LEVEL 1 LEVEL 2 LEVEL 3 NAV TOTAL Pension trust investments: Cash and short-term investments $ 275 $ 12 $ — $ — $ 287 Fixed income investments: Corporate — 1,054 — — 1,054 Government — 426 — — 426 Hedge fund and related investments — — 3 1,811 1,814 Private equity and related investments — — 65 1,014 1,079 Derivative instruments — 15 262 — 277 Total pension trust investments 275 1,507 330 2,825 4,937 Accrued liabilities, net (17 ) Pension trust net assets 4,920 Canadian nonregistered plan assets: Cash and short-term investments 5 — — — 5 Public equity investments 5 — — — 5 Total Canadian nonregistered plan assets 10 — — — 10 Total plan assets $ 4,930 Assets that do not have readily available quoted prices in an active market require more judgment to value and have increased valuation risk. As of December 31, 2019, $99 million, or 2.7 percent, of our pension plan assets were classified as Level 3 assets. A reconciliation of the beginning and ending balances of the pension plan assets measured at fair value using significant unobservable inputs (Level 3) is presented below: DOLLAR AMOUNTS IN MILLIONS INVESTMENTS Hedge funds and related investments Private equity and related investments Derivative instruments, net Total Balance as of December 31, 2017 $ 10 $ 102 $ 445 $ 557 Net realized gains (losses) — — 238 238 Net change in unrealized gains (losses) 1 (5 ) (184 ) (188 ) Purchases — 5 — 5 Sales — (2 ) — (2 ) Settlements — — (237 ) (237 ) Transfers into Level 3 — 18 — 18 Transfers out of Level 3 (8 ) (53 ) — (61 ) Balance as of December 31, 2018 3 65 262 330 Net realized gains (losses) 1 (1 ) 237 237 Net change in unrealized gains (losses) (1 ) — (262 ) (263 ) Purchases — — — — Sales (3 ) (3 ) — (6 ) Settlements — — (237 ) (237 ) Transfers into Level 3 13 28 — 41 Transfers out of Level 3 — (3 ) — (3 ) Balance as of December 31, 2019 $ 13 $ 86 $ — $ 99 The availability of observable market data is monitored to assess the appropriate classification of financial instruments within the fair value hierarchy. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, the transfer is reported at the beginning of the reporting period. We evaluate the significance of transfers between levels based upon the nature of the financial instrument and size of the transfer relative to total net assets available for benefits. The table below shows the fair value and aggregate notional amount of the derivative instruments held by our pension trusts at the end of the last two years. DOLLAR AMOUNTS IN MILLIONS FAIR VALUE NOTIONAL DECEMBER 31, 2019 DECEMBER 31, 2018 DECEMBER 31, 2019 DECEMBER 31, 2018 Foreign currency derivatives, net $ — $ — $ — $ 13 Futures contracts, net 10 15 813 1,073 Total return swaps, net — 262 — 558 Total $ 10 $ 277 $ 813 $ 1,644 ACTUARIAL ASSUMPTIONS We use actuarial assumptions to estimate our benefit obligations and our net periodic benefit costs. The following tables show the rates used to estimate our benefit obligations and periodic net benefit costs. Rates We Use in Estimating Our Benefit Obligations PENSION DECEMBER 31, 2019 DECEMBER 31, 2018 Discount rates: United States 3.40% 4.40% Canada 3.10% 3.70% Lump sum distributions (1)(2) PPA Table PPA Table Rate of compensation increase: Salaried: United States 13.00% to 2.00% decreasing with participant age 13.00% to 2.00% decreasing with participant age Canada 3.25% 3.25% Hourly: United States 13.00% to 2.30% decreasing with participant age 13.00% to 2.30% decreasing with participant age Canada 3.00% 3.00% Lump sum or installment distributions election (2) 60.00% 60.00% (1) PPA Phased Table: Interest and mortality assumptions as mandated by Pension Protection Act of 2006. (2) U.S. qualified salaried and nonqualified plans only. The discount rates used for our U.S. other postretirement benefit plans were 3.00 percent and 4.20 percent for the years ended December 31, 2019, and December 31, 2018, respectively. Additionally, the discount rates used for our Canadian other postretirement benefit plans were 3.00 percent and 3.70 percent for the years ended December 31, 2019, and December 31, 2018, respectively. Estimating Our Net Periodic Benefit Costs PENSION 2019 2018 2017 Discount rates: United States (1) 4.30% 3.70% 4.30% Canada 3.70% 3.50% 3.70% Lump sum distributions (2)(3) PPA Table PPA Table PPA Table Expected return on plan assets: Qualified/registered plans 7.00% 8.00% 8.00% Rate of compensation increase: Salaried: United States 13.00% to 2.00% decreasing with participant age 13.00% to 2.00% decreasing with participant age 13.00% to 2.00% decreasing with participant age Canada 3.25% 3.25% 3.50% Hourly: United States 13.00% to 2.30% decreasing with participant age 13.00% to 2.30% decreasing with participant age 13.00% to 2.30% decreasing with participant age Canada 3.00% 3.00% 3.25% Lump sum distributions election (3) 60.00% 60.00% 60.00% (1) In January 2019, we transferred approximately $1.5 billion of U.S. qualified pension plan assets and liabilities to an insurance company through the purchase of a group annuity contract. The settlement of this liability triggered a plan remeasurement, which caused a change in our 2019 pension plan discount rate. The initial discount rate used to estimate our net periodic benefit costs from January 1, 2019 through January 31, 2019 was 4.40 percent. As a result of the remeasurement, the discount rate was updated to 4.30 percent for the remainder of 2019. Refer to the “Actions to Reduce Pension Plan Obligations” section above for more details of this transaction. ( 2 ) PPA Phased Table: Interest and mortality assumptions as mandated by Pension Protection Act of 2006. ( 3 ) U.S. qualified salaried and nonqualified plans only. The discount rates used for our U.S. other postretirement benefit plans were 4.20 percent, 3.50 percent and 3.70 percent for the years ended December 31, 2019, December 31, 2018, and December 31, 2017, respectively. Additionally, the discount rates used for our Canadian other postretirement benefit plans were 3.70 percent, 3.40 percent and 3.60 percent for the years ended December 31, 2019, December 31, 2018, and December 31, 2017, respectively. Expected Return on Plan Assets Determining our expected return requires a high degree of judgment. We consider actual pension fund asset performance over multiple years, and current and expected valuation levels in the global equity and credit markets. Historical fund returns are used as a base and we place added weight on more recent pension plan asset performance. Qualified and Registered Pension Plans As discussed in the “Our Investment Policies and Strategies” section above, at the end of 2018, we began implementing a change in our asset strategy to an allocation that will more closely match the plan’s liability profile moving forward, resulting in a larger allocation of our assets into fixed income securities. With this change, we determined that it was appropriate to reduce our assumption of long-term rate of return on plan assets to 7.0 percent for the year ended December 31, 2019. As this strategy has been in place throughout 2019 and a larger percentage of our portfolio has been allocated to fixed income securities, we have determined that an additional reduction in our assumption of long-term rate of return on plan assets to 6.5 percent is appropriate for the year ended December 31, 2020. Health Care Costs Rising costs of health care affect the costs of our other postretirement plans. We use assumptions about health care cost trend rates to estimate the cost of benefits we provide. Our trend rate assumptions are based on historical market experience, current environment and future expectations. During 2019, the assumed weighted health care cost trend rate used to calculate the net periodic benefit cost was: • 7.8 • 4.5 percent for U.S. Health Reimbursement Account (HRA) • 4.9 percent for Canada This table shows the assumptions we use in estimating the annual cost increase for health care benefits we provide. Assumptions We Use in Estimating Health Care Benefit Obligations 2019 2018 U.S. CANADA U.S. CANADA Weighted health care cost trend rate assumed for next year 7.30% for Pre- Medicare and 4.50% for HRA 5.40% 7.80% for Pre- Medicare and 4.50% for HRA 4.90% Rate that the cost trend rate gradually declines to 4.50% 4.00% 4.50% 4.00% Year the cost trend rate is reached 2037 2039 2037 2039 ACTIVITY OF PLANS Net Periodic Benefit Cost (Credit) DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2017 2019 2018 2017 Net periodic benefit cost (credit): Service cost $ 32 $ 37 $ 35 $ — $ — $ — Interest cost 160 236 264 6 7 8 Expected return on plan assets (223 ) (399 ) (409 ) — — — Amortization of actuarial loss 112 225 195 7 8 8 Amortization of prior service cost (credit) 4 3 4 (5 ) (8 ) (8 ) Settlement charges 455 200 — — — — Net periodic benefit cost (credit) $ 540 $ 302 $ 89 $ 8 $ 7 $ 8 Expected Pension Plan and Benefit Funding Established funding standards govern the funding requirements for our qualified and registered pension plans. We fund the benefit payments of our nonqualified and nonregistered plans as benefit payments come due. We voluntarily contributed $300 million to our U.S. qualified pension plans during 2018, although there was no minimum required contribution for the year . During 2019, we contributed $10 million for our Canadian registered plans, we made contributions and benefit payments of $2 million for our Canadian nonregistered pension plans and made contributions and benefit payments of $18 million for our U.S. nonqualified pension plans. During 2020, based on estimated year-end asset values and projections of plan liabilities, we expect to: • be required to contribute approximately $2 million for our Canadian registered plan, • make contributions and benefit payments of approximately $17 million for our U.S. nonqualified pension plans and • make contributions and benefit payments of approximately $3 million for the Canadian non-registered plans. We do not anticipate contributions being required for our U.S. qualified pension plan for 2020. Expected Postretirement Benefit Funding During 2019, we contributed $11 million and $4 million to our U.S. and Canadian postretirement benefit plans, respectively. In 2020, we expect to make contributions of $9 million for our U.S. and Canadian other postretirement benefit plans, including $5 million expected to be required to cover benefit payments under collectively bargained contractual obligations. Estimated Projected Benefit Payments for the Next 10 Years DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2020 $ 237 $ 14 2021 $ 235 $ 13 2022 $ 236 $ 13 2023 $ 238 $ 12 2024 $ 237 $ 11 2025-2029 $ 1,176 $ 47 UNION-ADMINISTERED MULTIEMPLOYER BENEFIT PLANS We contribute to multiemployer defined benefit plans under the terms of collective-bargaining agreements. These plans cover a small number of our employees and on an annual basis our contributions are immaterial. These plans have different risks than single-employer plans. Our contributions may be used to fund benefits for employees of other participating employers. If we choose to stop participating, we may be required to pay a withdrawal liability based on the underfunded status of the plan . DEFINED CONTRIBUTION PLANS We sponsor various defined contribution plans for our U.S. and Canadian salaried and hourly employees. Our contributions to these plans were: • $25 million in 2019, • $22 million in 2018 and • $21 million in 2017.

ACCRUED LIABILITIES

ACCRUED LIABILITIES	12 Months Ended
	Dec. 31, 2019
Accrued Liabilities Current [Abstract]
ACCRUED LIABILITIES	NOTE 10: ACCRUED LIABILITIES Accrued liabilities were comprised of the following: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Compensation and employee benefit costs $ 188 $ 192 Current portion of lease liabilities ( Note 17 ) 33 — Customer rebates, volume discounts and deferred income 105 99 Interest 98 109 Taxes payable 24 30 Other 82 60 Total $ 530 $ 490

LINES OF CREDIT

LINES OF CREDIT	12 Months Ended
	Dec. 31, 2019
Short Term Debt Other Disclosures [Abstract]
LINES OF CREDIT	NOTE 11: LINE OF CREDIT OUR LINE OF CREDIT In March 2017, we entered into a $1.5 billion five-year senior unsecured revolving credit facility that expires in March 2022 In January 2020, we amended and restated our $1.5 billion five-year senior unsecured revolving credit facility, which now expires in January 2025 LETTERS OF CREDIT AND SURETY BONDS The amounts of letters of credit and surety bonds we have entered into as of the end of the last two years are included in the following table: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Letters of credit $ 35 $ 38 Surety bonds $ 127 $ 123 Our compensating balance requirements for our letters of credit were $3 million and $6 million as of December 31, 2019 and December 31, 2018, respectively.

LONG-TERM DEBT

LONG-TERM DEBT	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
LONG-TERM DEBT	NOTE 12: LONG-TERM DEBT This note provides details about: • debt issued and extinguished and • long-term debt and related maturities. Our long-term debt includes notes, debentures and other borrowings. DEBT ISSUED AND EXTINGUISHED In February 2019, we issued $750 million of 4.00 percent notes due in November 2029. The net proceeds after deducting the discount, underwriting fees and issuance costs were $739 million. In March 2019, a portion of the net proceeds was used to redeem our $500 million 7.38 percent note due October 2019. A pretax charge of $12 million was included in "Interest expense, net of capitalized interest" on our Consolidated Statement of Operations during first quarter 2019 for make-whole premiums, unamortized debt issuance costs and unamortized debt discounts in connection with the early extinguishment of the $500 million note. During February 2018, we paid our $62 million 7.00 debenture at maturity. LONG-TERM DEBT AND RELATED MATURITIES The following table lists our long-term debt by types and interest rates at the end of our last two years and includes the current portion. Long-Term Debt by Types and Interest Rates (Includes Current Portion) DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 7.375% notes due 2019 $ — $ 500 9.00% debentures due 2021 150 150 4.70% debentures due 2021 569 569 7.125% debentures due 2023 191 191 5.207% debentures due 2023 860 860 4.625% notes due 2023 500 500 3.25% debentures due 2023 325 325 8.50% debentures due 2025 300 300 7.95% debentures due 2025 136 136 7.70% debentures due 2026 150 150 7.35% debentures due 2026 62 62 7.85% debentures due 2026 100 100 Variable-rate term loan credit facility matures 2026 225 225 6.95% debentures due 2027 300 300 4.00% notes due 2029 750 — 7.375% debentures due 2032 1,250 1,250 6.875% debentures due 2033 275 275 Other 1 1 Total principal long-term debt 6,144 5,894 Add: fair value adjustments (related to Plum Creek merger) 27 39 Less: unamortized discounts (14 ) (5 ) Less: unamortized debt expense (10 ) (9 ) Total $ 6,147 $ 5,919 Portion due within one year $ — $ 500 Amounts of Long-Term Debt Due Annually for the Next Five Years and Thereafter DOLLAR AMOUNTS IN MILLIONS (1) 2020 $ — 2021 $ 719 2022 $ — 2023 $ 1,876 2024 $ — Thereafter $ 3,549 (1) Excludes $3 million of unamortized discounts, capitalized debt expense and fair value adjustments (related to Plum Creek merger).

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	12 Months Ended
	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	NOTE 13: FAIR VALUE OF FINANCIAL INSTRUMENTS FAIR VALUE OF DEBT The estimated fair values and carrying values of our long-term debt and line of credit consisted of the following: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 CARRYING VALUE FAIR VALUE (LEVEL 2) CARRYING VALUE FAIR VALUE (LEVEL 2) Long-term debt (including current maturities) and line of credit: Fixed rate $ 5,922 $ 6,986 $ 5,694 $ 6,345 Variable rate 455 455 650 650 Total Debt $ 6,377 $ 7,441 $ 6,344 $ 6,995 To estimate the fair value of long-term debt we used the market approach, which is based on quoted market prices we received for the same types and issues of our debt. We believe that our variable-rate long-term debt and line of credit instruments have net carrying values that approximate their fair values with only insignificant differences. The inputs to these valuations are based on market data obtained from independent sources or information derived principally from observable market data. The difference between the fair value and the carrying value represents the theoretical net premium or discount we would pay or receive to retire all debt at the measurement date. FAIR VALUE OF OTHER FINANCIAL INSTRUMENTS We believe that our other financial instruments, including cash and cash equivalents, short-term investments, mutual fund investments held in grantor trusts, receivables and payables, have net carrying values that approximate their fair values with only insignificant differences. This is primarily due to the short-term nature of these instruments and the allowance for doubtful accounts.

LEGAL PROCEEDINGS, COMMITMENTS

LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES	NOTE 14: LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES This note provides details about our: • legal proceedings, • environmental matters and • commitments and other contingencies. LEGAL PROCEEDINGS We are party to various legal proceedings arising in the ordinary course of business. We are not currently a party to any legal proceeding that management believes could have a material adverse effect on our Consolidated Balance Sheet , Consolidated Statement of Operations or Consolidated Statement of Cash Flows . ENVIRONMENTAL MATTERS Site Remediation Under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) – commonly known as Superfund – and similar state laws, we are a party to various proceedings related to the cleanup of hazardous waste sites and have been notified that we may be a potentially responsible party related to the cleanup of other hazardous waste sites for which proceedings have not yet been initiated. We have received notification from the Environmental Protection Agency (the EPA) and have acknowledged that we are a potentially responsible party in a portion of the Kalamazoo River Superfund site in southwest Michigan. Our involvement in the remediation site is based on our former ownership of the Plainwell, Michigan mill located within the remediation site. Several other companies also have been deemed potentially responsible parties as past or present owners or operators of facilities within the site, or as arrangers under CERCLA. We cooperated with other parties to jointly implement an administrative order issued by the EPA on April 14, 2016, with respect to a portion of the site comprising a stretch of the river approximately 1.7 miles long referred to as the Otsego Township Dam Area. During third quarter 2018, implementation of this administrative order was completed. In 2010, the company, along with others, was named as a defendant by Georgia-Pacific Consumer Products LP, Fort James Corporation and Georgia-Pacific LLC in an action seeking contribution under CERCLA for remediation costs relating to a certain area within the site. On March 29, 2018, the U.S. District Court issued an opinion and order assigning the company responsibility for 5 percent of approximately $50 million in past costs incurred by the plaintiffs. The remaining 95 percent of this pool of past costs incurred was allocated to the plaintiffs and other defendants. The opinion and order, which is currently on appeal before the U.S. Court of Appeals for the Sixth Circuit, does not establish allocation for future remediation costs, and accordingly, we may incur additional costs in connection with future remediation tasks for other areas of the site. In connection with the opinion and order, we updated our best estimate of the liability associated with the site and recorded a pretax charge of $28 million in first quarter 2018 within "Other operating costs (income), net" on our Consolidated Statement of Operations . Our Established Reserves. We have established reserves for estimated remediation costs on the active Superfund sites and other sites for which we are a potentially responsible party. These reserves are recorded in "Accrued liabilities" and "Other liabilities" on our Consolidated Balance Sheet . Changes in the Reserve for Environmental Remediation DOLLAR AMOUNTS IN MILLIONS Reserve balance as of December 31, 2018 $ 62 Reserve charges and adjustments, net 4 Payments (5 ) Reserve balance as of December 31, 2019 $ 61 We change our reserve to reflect: • new information on any site concerning implementation of remediation alternatives, • updates on prior cost estimates and new sites and • costs incurred to remediate sites. Estimates. We believe it is reasonably possible, based on currently available information and analysis, that remediation costs for all identified sites may exceed our existing reserves by up to $124 million. This estimate, in which those additional costs may be incurred over several years, is the upper end of the range of reasonably possible additional costs. The estimate: • is much less certain than the estimates on which our accruals currently are based and • uses assumptions that are less favorable to us among the range of reasonably possible outcomes. In estimating our current accruals and the possible range of additional future costs, we: • assumed we will not bear the entire cost of remediation of every site, • took into account the ability of other potentially responsible parties to participate and • considered each party’s financial condition and probable contribution on a per-site basis. We have not recorded any amounts for potential recoveries from insurance carriers. Asset Retirement Obligations We have obligations associated with the retirement of tangible long-lived assets consisting primarily of reforestation obligations related to forest management licenses in Canada and obligations to close and cap landfills. Some of our sites have asbestos containing materials. We have met our current legal obligation to identify and manage these materials. In situations where we cannot reasonably determine when asbestos containing materials might be removed from the sites, we have not recorded an accrual because the fair value of the obligation cannot be reasonably estimated. As of December 31, 2019, and December 31, 2018, we had an asset retirement obligation reserve of $30 million and $29 million, respectively. These obligations are recorded in "Accrued liabilities" and "Other liabilities" on our Consolidated Balance Sheet . COMMITMENTS AND OTHER CONTINGENCIES Product Remediation Contingency Refer to Note 19: Charges (Recoveries) for Product Remediation, Net for further information.

SHAREHOLDERS' INTEREST

SHAREHOLDERS' INTEREST	12 Months Ended
	Dec. 31, 2019
Stockholders Equity Note [Abstract]
SHAREHOLDERS' INTEREST	NOTE 15: SHAREHOLDERS’ INTEREST This note provides details about: • preferred and preference shares, • common shares, • share repurchase programs and • accumulated other comprehensive loss. PREFERRED AND PREFERENCE SHARES We had no preferred shares or preference shares outstanding as of December 31, 2019, or December 31, 2018. We have authorization to issue 7 million preferred shares with a par value of $1.00 per share and 40 million preference shares with a par value of $1.00 per share. COMMON SHARES The number of common shares we have outstanding changes when: • new shares are issued, • stock options are exercised, • restricted stock units or performance share units vest, • stock equivalent units are paid out, • shares are tendered, • shares are repurchased or • shares are canceled. Reconciliation of Our Common Share Activity SHARES IN THOUSANDS 2019 2018 2017 Outstanding at beginning of year 746,391 755,223 748,528 Stock options exercised 660 2,026 5,970 Issued for vested restricted stock units 480 466 605 Issued for vested performance share units 118 86 120 Repurchased (2,349 ) (11,410 ) — Outstanding at end of year 745,300 746,391 755,223 SHARE REPURCHASE PROGRAMS On February 7, 2019, our board of directors terminated the 2016 Repurchase Program and approved a new share repurchase program (the 2019 Repurchase Program) under which we are authorized to repurchase up to $500 million of outstanding shares. During 2019, we repurchased over 2.3 million shares of common stock for approximately $60 million (including transaction fees) under the 2019 Repurchase Program. As of December 31, 2019, we have remaining authorization of $440 million for future stock repurchases. During 2018, we repurchased over 11.4 million shares of common stock for approximately $366 million (including transaction fees) under the 2016 Repurchase Program. As of December 31, 2018, we had remaining authorization of $135 million for future stock repurchases. We did not repurchase any shares of common stock during 2017. All common stock repurchases under the 2016 and 2019 Repurchase Programs were made in open-market transactions. We record share repurchases upon trade date as opposed to the settlement date when cash is disbursed. We record a liability to account for repurchases that have not been cash settled. There were no unsettled repurchases as of December 31, 2019, or December 31, 2018. ACCUMULATED OTHER COMPREHENSIVE LOSS Changes in amounts included in our accumulated other comprehensive loss by component are: DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Pension (1) Balance at beginning of period $ (1,343 ) $ (1,810 ) $ (1,660 ) Other comprehensive income (loss) before reclassifications (216 ) 388 (282 ) Amounts reclassified from accumulated other comprehensive income (loss) to earnings (2)(3) 431 325 132 Total other comprehensive income (loss) 215 713 (150 ) Reclassification of certain effects due to tax law changes (4) — (246 ) — Balance at end of period (1,128 ) (1,343 ) (1,810 ) Other Postretirement Benefits (1) Balance at beginning of period (19 ) (25 ) (38 ) Other comprehensive income (loss) before reclassifications 6 13 14 Amounts reclassified from accumulated other comprehensive income (loss) to earnings (2) 1 — (1 ) Total other comprehensive income (loss) 7 13 13 Reclassification of certain tax effects due to tax law changes (4) — (7 ) — Balance at end of period (12 ) (19 ) (25 ) Translation Adjustments and Other Balance at beginning of period 210 273 239 Translation adjustments 26 (54 ) 34 Total other comprehensive income (loss) 26 (54 ) 34 Reclassification of accumulated unrealized gains on available-for-sale securities (5) — (9 ) — Balance at end of period 236 210 273 Accumulated other comprehensive loss, end of period $ (904 ) $ (1,152 ) $ (1,562 ) (1) Amounts are presented net of tax. (2) Amounts of actuarial loss and prior service (cost) credit are components of net periodic benefit cost (credit). See Note 9: Pension and Other Postretirement Benefit Plans . (3) Amounts include settlement charges totaling $455 million and $200 million related to our pension plans for the years ended December 31, 2019 and December 31, 2018, respectively. See Note 9: Pension and Other Postretirement Benefit Plans for further detail. (4) During 2018, we reclassified certain tax effects from tax law changes of $253 million from "Accumulated other comprehensive loss" to "Retained earnings" on our Consolidated Balance Sheet in accordance with ASU 2018-02. (5) During 2018, we reclassified accumulated unrealized gains on available-for-sale securities of $9 million from "Accumulated other comprehensive loss" to "Retained earnings" on our Consolidated Balance Sheet in accordance with ASU 2016-01.

SHARE-BASED COMPENSATION

SHARE-BASED COMPENSATION	12 Months Ended
	Dec. 31, 2019
Share Based Compensation [Abstract]
SHARE-BASED COMPENSATION	NOTE 16: SHARE-BASED COMPENSATION This note provides details about: • our Long-Term Incentive Compensation Plan (2013 Plan), • how we account for share-based awards, • tax benefits of share-based awards, • types of share-based compensation, • unrecognized share-based compensation and • deferred compensation stock equivalent units. Share-based compensation expense was: • $30 million in 2019, • $42 million in 2018 and • $40 million in 2017. OUR LONG-TERM INCENTIVE COMPENSATION PLAN Our long-term incentive plan provides for share-based awards that include: • restricted stock, • restricted stock units (RSUs), • performance shares, • performance share units (PSUs), • stock options and • stock appreciation rights (SARs). We may issue future grants of up to 20 million shares under the 2013 Plan. We also have the right to reissue forfeited and expired grants. For restricted stock, RSUs, performance shares, PSUs or other equity grants: • An individual participant may receive a grant of up to 1 million shares annually. • No participant may be granted awards that exceed $10 million earned in a 12-month period. For stock options and SARs: • An individual participant may receive a grant of up to 2 million shares in any one calendar year. • The exercise price is required to be the market price on the date of the grant. We have not granted any stock options or SARs since 2016 and the remaining liability related to SARs is immaterial at December 31, 2019. The Compensation Committee of our board of directors annually establishes an overall pool of stock awards available for grants based on performance. For stock-settled awards we: • issue new stock into the marketplace and • generally do not repurchase shares in connection with issuing new awards. Our common shares would increase by approximately 28 million shares if all share-based awards were exercised or vested. These include: • all options, RSUs and PSUs outstanding at December 31, 2019, and • all remaining options, RSUs and PSUs that could be granted under the 2013 Plan. HOW WE ACCOUNT FOR SHARE-BASED AWARDS When accounting for share-based awards we: • use a fair-value-based measurement and • recognize the cost of share-based awards on our consolidated financial statements. We recognize the cost of share-based awards on our Consolidated Statement of Operations over the required service period — generally the period from the date of the grant to the date when it is fully vested. Special situations include: • Awards that vest upon retirement — the required service period ends on the date an employee is eligible for retirement, including early retirement. • Awards that continue to vest following job elimination or the sale of a business — the required service period ends on the date the employment from the company is terminated. In these special situations, compensation expense from share-based awards is recognized over a period that is shorter than the stated vesting period. TAX BENEFITS OF SHARE-BASED AWARDS Our total income tax benefit from share-based awards recognized on our Consolidated Statement of Operations for the last three years was: • $4 million in 2019, • $5 million in 2018 and • $6 million in 2017. Tax benefits from share-based awards are accrued as stock compensation expense and realized when: • restricted shares and RSUs vest, • performance shares and PSUs vest, • stock options are exercised and • SARs are exercised. TYPES OF SHARE-BASED COMPENSATION Our share-based compensation is in the form of: • RSUs, • PSUs, • stock options and • SARs. RESTRICTED STOCK UNITS Through the 2013 Plan, we award RSUs — grants that entitle the holder to shares of our stock as the award vests. The Details Our RSUs granted in 2019, 2018 and 2017 generally: • vest ratably over four years • immediately vest in the event of death while employed or disability; • continue to vest upon retirement at an age of at least 62, but a portion of the grant is forfeited if retirement occurs before the one-year anniversary of the grant; • continue vesting for one year in the event of involuntary termination when retirement has not been met and • will be forfeited upon termination of employment in all other situations including early retirement prior to age 62. Our Accounting The fair value of our RSUs is the market price of our stock on the grant date of the awards. We generally record share-based compensation expense for RSUs over the four-year vesting period. Generally, for RSUs that continue to vest following the termination of employment, we record the share-based compensation expense over a required service period that is less than the stated vesting period. Activity The following table shows our RSU activity for 2019: RESTRICTED STOCK UNITS (IN THOUSANDS) WEIGHTED AVERAGE GRANT-DATE FAIR VALUE Nonvested at December 31, 2018 1,593 $ 31.41 Granted 865 $ 25.83 Vested (582 ) $ 30.34 Forfeited (87 ) $ 29.40 Nonvested at December 31, 2019 (1) 1,789 $ 29.15 ( 1) As of December 31, 2019, there were approximately 526 thousand RSUs that had met the requisite service period and will be released as identified in the grant terms. The weighted average grant-date fair value for RSUs was: • $25.83 in 2019, • $34.19 in 2018 and • $32.83 in 2017. The total grant-date fair value of RSUs vested was: • $18 million in 2019, • $16 million in 2018 and • $18 million in 2017. Nonvested RSUs accrue dividends that are paid out when RSUs vest. Any RSUs forfeited will not receive dividends. As RSUs vest, a portion of the shares awarded is withheld to cover employee taxes. As a result, the number of stock units vested and the number of common shares issued will differ. PERFORMANCE SHARE UNITS Through the 2013 Plan, we award PSUs — grants that entitle the holder to shares of our stock as the award vests. The Details The final number of shares awarded will range from 0 percent to 150 percent of each grant’s target, depending upon actual company performance. For PSUs granted in 2019, 2018 and 2017, the ultimate number of shares earned is based on two measures: • our relative total shareholder return (TSR) ranking measured against the S&P 500 over a three-year period and • our relative TSR ranking measured against an industry peer group of companies over a three-year period. The vesting provisions for PSUs granted in 2019, 2018 and 2017 were as follows: • vest 100 percent on the third anniversary of the grant date as long as the individual remains employed by the company; • fully vest in the event the participant dies or becomes disabled while employed; • continue to vest upon retirement at an age of at least 62, but a portion of the grant is forfeited if retirement occurs before the one-year anniversary of the grant; • continue vesting for one year in the event of involuntary termination when the retirement criteria has not been met and the employee has met the second anniversary of the grant date and • will be forfeited upon termination of employment in all other situations including early retirement prior to age 62. Our Accounting Since the awards contain a market condition, the effect of the market condition is reflected in the grant-date fair value which is estimated using a Monte Carlo simulation model. This model estimates the TSR ranking of the company over the performance period. Compensation expense is based on the estimated probable number of earned awards and recognized over the vesting period on an accelerated basis. Generally, compensation expense would be reversed if the performance condition is not met unless the requisite service period has been achieved. Weighted Average Assumptions Used in Estimating the Value of PSUs 2019 GRANTS 2018 GRANTS 2017 GRANTS Performance period 1/1/2019-12/31/2021 1/1/2018-12/31/2020 1/1/2017-12/31/2019 Expected dividends 5.25% 3.81% 3.74% Risk-free rate 2.43% - 2.55% 1.75% - 2.34% 0.68% - 1.55% Volatility 22.50% - 27.40% 17.30% - 21.52% 22.71% - 24.07% Weighted average grant-date fair value $ 29.66 $ 35.49 $ 37.93 Activity The following table shows our PSU activity for 2019: GRANTS (IN THOUSANDS) WEIGHTED AVERAGE GRANT-DATE FAIR VALUE Nonvested at December 31, 2018 1,042 $ 31.52 Granted at target 419 29.66 Vested (153 ) 22.80 Forfeited (26 ) 34.05 Performance adjustment (233 ) 22.80 Nonvested at December 31, 2019 (1) 1,049 $ 33.93 (1) As of December 31, 2019, there were approximately 519 thousand PSUs that had met the requisite service period and will be released as identified in the grant terms. The total grant-date fair value of PSUs vested was: • $3 million in 2019, • $4 million in 2018 and • $4 million in 2017. As PSUs vest, a portion of the shares awarded is withheld to cover participant taxes. As a result, the number of stock units vested and the number of common shares issued will differ. STOCK OPTIONS Stock options entitle award recipients to purchase shares of our common stock at a fixed exercise price. We have not granted stock option awards since 2016. When granted in prior years, stock options had an exercise price equal to the market price of our stock on the date of the grant. The Details Our stock options generally: • vest over four years of continuous service, • must be exercised within 10 years of the grant date and • use a Black-Scholes option valuation model to estimate the fair value of every stock option award on its grant date. Activity The following table shows our stock option activity for 2019: OPTIONS (IN THOUSANDS) WEIGHTED AVERAGE EXERCISE PRICE WEIGHTED AVERAGE REMAINING CONTRACTUAL TERM (IN YEARS) AGGREGATE INTRINSIC VALUE (IN MILLIONS) Outstanding at December 31, 2018 6,366 $ 26.75 Exercised (661 ) $ 19.16 Forfeited or expired (430 ) $ 31.63 Outstanding at December 31, 2019 (1) 5,275 $ 27.30 4.61 $ 21 Exercisable at December 31, 2019 4,678 $ 27.84 4.42 $ 17 (1) As of December 31, 2019, there were approximately 324 thousand stock options that had met the requisite service period and will be released as identified in the grant terms. The total intrinsic value of stock options exercised was: • $5 million in 2019, • $22 million in 2018 and • $68 million in 2017. UNRECOGNIZED SHARE-BASED COMPENSATION As of December 31, 2019, our unrecognized share-based compensation cost for all types of share-based awards included $36 million related to non-vested equity-classified share-based compensation arrangements. These are expected to be recognized over a weighted average period of approximately 1.2 years. DEFERRED COMPENSATION STOCK EQUIVALENT UNITS Certain employees and our board of directors may defer compensation into stock equivalent units. The Details Eligible employees: • may choose to defer all or part of their bonus into stock equivalent units; • may choose to defer part of their salary, except for executive officers and • receive a 15 percent premium if the deferral is for at least five years. Our directors: • receive a portion of their annual retainer fee in the form of RSUs, which vest over one year and may be deferred into stock equivalent units; • may choose to defer some or all of the remainder of their annual retainer fee into stock equivalent units and • do not receive a premium for their deferrals. Employees and directors also choose when the deferrals will be paid out, although no deferrals may be paid until after the separation from service of the employee or director. Our Accounting We settle all deferred compensation accounts in cash for our employees. Our directors receive shares of common stock as payment for stock equivalent units. In addition, we credit all stock equivalent accounts with dividend equivalents. The number of common shares to be issued in the future to directors is 674 thousand. Stock equivalent units are: • liability-classified awards and • remeasured to fair value at every reporting date. The fair value of a stock equivalent unit is equal to the market price of our stock. Activity The number of stock equivalent units outstanding in our deferred compensation accounts was: • 788 • 788 • 804

LEASES

LEASES	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
LEASES	NOTE 17: LEASES We account for leases in accordance with ASC Topic 842, Leases Consolidated Balance Sheet on January 1, 2019. The majority of our operating leases are related to our office and warehouse space, and the majority of our financing leases are related to vehicles and forklifts. Our leases have remaining lease terms of approximately 1 year to 25 years. Options to renew, extend or terminate a lease are reflected in our lease terms when we believe it is reasonably certain we will exercise that option. When our leases do not provide an implicit or an explicit interest rate, we use our incremental borrowing rate in determining the present value of lease payments. Lease Expense DOLLAR AMOUNTS IN MILLIONS 2019 Operating lease costs $ 20 Financing lease costs 15 Total lease costs $ 35 Supplemental Cash Flow Information DOLLAR AMOUNTS IN MILLIONS 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 20 Financing cash flows for financing leases (1) $ 16 ROU assets obtained in exchange for new (modified) lease liabilities: Operating leases $ 6 Financing leases $ 5 (1) Interest expense related to financing leases was immaterial during 2019. Supplemental Balance Sheet Information Related to Leases DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 LEASES BALANCE SHEET CLASSIFICATION Assets Operating lease ROU assets Other assets $ 120 Financing lease ROU assets Property and equipment, net 28 Total leased assets $ 148 Liabilities Current: Operating lease liabilities Accrued liabilities $ 20 Financing lease liabilities Accrued liabilities 13 Noncurrent: Operating lease liabilities Other liabilities 103 Financing lease liabilities Other liabilities 20 Total lease liabilities $ 156 Weighted Average Remaining Lease Term DECEMBER 31, 2019 Operating leases 11 years Financing leases 3 years Weighted Average Discount Rate DECEMBER 31, 2019 Operating leases 4.2% Financing leases 3.1% Maturities of Lease Liabilities as of December 31, 2019 DOLLAR AMOUNTS IN MILLIONS OPERATING LEASES FINANCING LEASES 2020 $ 20 $ 14 2021 18 10 2022 17 7 2023 16 4 2024 12 — Thereafter 70 — Total lease payments 153 35 Less: interest (30 ) (2 ) Total present value of lease liabilities $ 123 $ 33 Operating Lease Commitments as of December 31, 2018 DOLLAR AMOUNTS IN MILLIONS 2019 $ 35 2020 $ 29 2021 $ 26 2022 $ 24 2023 $ 18 Thereafter $ 78

CHARGES FOR INTEGRATION AND RES

CHARGES FOR INTEGRATION AND RESTRUCTURING, CLOSURES AND ASSET IMPAIRMENTS	12 Months Ended
	Dec. 31, 2019
Restructuring Costs And Asset Impairment Charges [Abstract]
CHARGES FOR INTEGRATION AND RESTRUCTURING, CLOSURES AND ASSET IMPAIRMENTS	NOTE 18: CHARGES FOR INTEGRATION AND RESTRUCTURING, CLOSURES AND ASSET IMPAIRMENTS INTEGRATION, RESTRUCTURING AND CLOSURES During 2017, we incurred and accrued a total of $34 million for termination benefits (primarily severance), non-recurring professional services and other costs directly attributable to our merger with Plum Creek. Other restructuring and closure costs totaled $6 million in 2017, which included lease termination charges, dismantling and demolition of plant and equipment, gain or loss on disposition of assets, environmental cleanup costs and incremental costs to wind down operating facilities. ASSET IMPAIRMENTS The “Impairment of Long-Lived Assets” section of Note 1: Summary of Significant Accounting Policies Critical Accounting Policies . In 2019, we recognized an impairment charge of $80 million related to our Montana timberlands assets. On December 17, 2019, we announced an agreement to sell 630,000 acres of Montana timberlands, and the related assets met the relevant criteria to be classified as held for sale as of December 31, 2019. This designation required us to record the related assets at fair value, less an amount of estimated selling costs, and thus recognize an $80 million noncash pretax impairment charge in the Timberlands segment. The fair value of the related assets was primarily based on the agreed upon cash purchase price of $145 million. In 2017, we recognized an impairment charge of $147 million related to the timberlands and manufacturing assets of our Uruguay operations. Refer to Note 4: Divestitures and Assets Held for Sale for further details on the assets held for sale and the sale of our Uruguay operations. Additionally, in 2017, we recognized a small impairment charge related to a nonstrategic asset in our Wood Products segment. The fair value of the asset was determined using the value indicated in a purchase and sale agreement.

CHARGES (RECOVERIES) FOR PRODUC

CHARGES (RECOVERIES) FOR PRODUCT REMEDIATION, NET	12 Months Ended
	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
CHARGES (RECOVERIES) FOR PRODUCT REMEDIATION, NET	NOTE 19: CHARGES (RECOVERIES) FOR PRODUCT REMEDIATION, NET In July 2017, we announced we were implementing a solution to address concerns regarding our TJI® Joists coated with our former Flak Jacket® Protection product. This issue was isolated to Flak Jacket product manufactured after December 1, 2016 and did not affect any of our other products. During the year ended December 31, 2019, we received and recorded an insurance recovery of $68 million related to our remediation efforts. In addition, we recorded insurance recoveries of $25 million and product remediation charges of $25 million during the year ended December 31, 2018. During the year ended December 31, 2017, we recorded $290 million for expected costs associated with the remediation. The charges and recoveries recorded are attributable to our Wood Products segment and were recorded in "Charges (recoveries) for product remediation, net" on the Consolidated Statement of Operations .

OTHER OPERATING COSTS (INCOME),

OTHER OPERATING COSTS (INCOME), NET	12 Months Ended
	Dec. 31, 2019
Other Income [Abstract]
OTHER OPERATING COSTS (INCOME), NET	NOTE 20: OTHER OPERATING COSTS (INCOME), NET Other operating costs (income), net: • includes both recurring and non-recurring income and expense items and • can fluctuate from year to year. Income and Expense Items Included in Other Operating Costs (Income), Net DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Environmental remediation insurance recoveries $ — $ (5 ) $ (42 ) Foreign exchange losses (gains), net (1) 2 (3 ) (1 ) Gain on disposition of nonstrategic assets (4 ) (5 ) (16 ) Gain on sale of timberlands (2) (48 ) — (99 ) Litigation expense, net 63 35 20 Research and development expenses 6 8 14 Other, net (3) 28 52 10 Total other operating costs (income), net $ 47 $ 82 $ (114 ) (1) Foreign exchange gains and losses result from changes in exchange rates primarily related to our U.S. dollar denominated cash and debt balances that are held by our Canadian subsidiary. (2) The 2019 gain on sale of timberlands relates to the sale of our Michigan timberlands during fourth quarter 2019. The 2017 amount relates to 100,000 acres sold to Twin Creeks during fourth quarter 2017. Refer to Note 4: Divestitures and Assets Held for Sale Note 8: Related Parties (3) "Other, net" includes environmental remediation charges. See Note 14: Legal Proceedings, Commitments and Contingencies for more information.

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
INCOME TAXES	NOTE 21: INCOME TAXES This note provides details about income taxes applicable to our operations, including the following: • earnings before income taxes, • provision for income taxes, • effective income tax rate, • deferred tax assets and liabilities, • unrecognized tax benefits and • resolution of IRS tax matter. The Income Taxes section of Note 1: Summary of Significant Accounting Policies provides details about how we account for our income taxes. EARNINGS (LOSS) BEFORE INCOME TAXES Domestic and Foreign Earnings (Loss) Before Income Taxes DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Domestic earnings (loss) $ (268 ) $ 556 $ 643 Foreign earnings 55 251 73 Total earnings (loss) before income taxes $ (213 ) $ 807 $ 716 PROVISION (BENEFIT) FOR INCOME TAXES Provision (Benefit) for Income Taxes DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Current: Federal $ 21 $ (69 ) $ 10 State 1 (5 ) — Foreign 10 61 82 Total current 32 (13 ) 92 Deferred: Federal (137 ) 45 61 State (31 ) 12 (18 ) Foreign (1 ) 15 (1 ) Total deferred (169 ) 72 42 Total income tax provision (benefit) $ (137 ) $ 59 $ 134 EFFECTIVE INCOME TAX RATE Effective Income Tax Rate DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 U.S. federal statutory income tax $ (45 ) $ 170 $ 250 State income taxes, net of federal tax benefit (31 ) 8 (2 ) REIT income not subject to federal income tax (68 ) (116 ) (198 ) SDT settlement (1) — 21 — Tax effect of U.S. corporate rate change (2) — — 74 Voluntary pension contribution (3) — (41 ) — Return to provision adjustment 4 (1 ) 2 Foreign taxes (2 ) 15 54 Repatriation of Canadian earnings — — (22 ) Other, net 5 3 (24 ) Total income tax provision (benefit) $ (137 ) $ 59 $ 134 Effective income tax rate 64.1% 7.3% 18.8% (1) In fourth quarter 2018, we recorded tax expense of $21 million related to the settlement of a dispute with the IRS. Refer to “Resolution of IRS Matter” below for further information. (2) In December 2017, H.R. 1 (the Tax Act) was enacted. The Tax Act contained significant changes to corporate taxation, including a reduction in the corporate tax rate from 35 percent to 21 percent. As a result of this change, we revalued our deferred tax assets and liabilities and recorded tax expense of $74 million during 2017, which reduced our net deferred tax asset. (3) At the end of 2017, we revalued our deferred tax assets and liabilities to the 21 percent federal tax rate prescribed by the Tax Act. During 2018, we made a voluntary contribution of $300 million to our U.S. qualified pension plan. We deducted this contribution on our 2017 U.S. federal tax return at the 2017 federal tax rate of 35 percent. This resulted in an incremental $41 million tax benefit for the portion attributable to our TRSs. Refer to Note 9: Pension and Other Postretirement Benefit Plans for further information on the voluntary contribution. DEFERRED TAX ASSETS AND LIABILITIES Deferred tax assets and liabilities reflect the future tax effect created by differences between the timing of when income or deductions are recognized for pretax financial book reporting purposes versus income tax purposes. Deferred tax assets represent a future tax benefit (or reduction to income taxes in a future period), while deferred tax liabilities represent a future tax obligation (or increase to income taxes in a future period). Balance Sheet Classification of Deferred Income Tax Assets (Liabilities) DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Net noncurrent deferred tax asset $ 72 $ 15 Net noncurrent deferred tax liability (6 ) (43 ) Net deferred tax asset (liability) $ 66 $ (28 ) Items Included in Our Deferred Income Tax Assets (Liabilities) DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Deferred tax assets: Pension and postretirement benefits $ 159 $ 112 State tax credits 53 51 Depletion 34 41 Excess interest 55 30 Incentive compensation 17 20 Workers compensation 18 18 Net operating loss carryforwards 28 19 Other 101 96 Gross deferred tax assets 465 387 Valuation allowance (64 ) (61 ) Net deferred tax assets 401 326 Deferred tax liabilities: Property, plant and equipment (224 ) (197 ) Timber installment notes (74 ) (116 ) Other (37 ) (41 ) Net deferred tax liabilities (335 ) (354 ) Net deferred tax asset (liability) $ 66 $ (28 ) Net Operating Loss and Credit Carryforwards Our gross federal, state and foreign net operating loss carryforwards as of December 31, 2019 totaled $850 million as follows: • Federal - U.S. REIT - $302 million, which expire from 2034 through 2036 • State - $548 million, which will begin to expire in 2022; • Foreign - none currently recorded Our gross state credit carryforwards as of December 31, 2019 totaled $67 million, which includes $16 million that expire from 2020 through 2033 and $51 million that do not expire. Our U.S. TRSs have $7 million in foreign tax credit carryforwards that expire from 2027 through 2028. Valuation Allowances With the exception of the valuation allowance discussed below, we believe it is more likely than not that we will have sufficient future taxable income to realize our deferred tax assets. Our valuation allowance on our deferred tax assets was $64 million as of December 31, 2019, which related to state credits, state net operating losses and passive foreign tax credits. Reinvestment of Undistributed Earnings Starting in 2018, we revised our indefinite reinvestment assertion regarding the earnings of our Canadian subsidiary to permanently reinvest approximately 10 percent of its earnings. Our change in assertion was based on the company’s review of global cash management and planned capital deployment, taking into consideration the effects of the Tax Act. We have no other foreign subsidiaries with undistributed earnings. Accordingly, deferred taxes have been provided primarily related to Canadian withholding taxes associated with Canadian earnings no longer considered permanently reinvested. UNRECOGNIZED TAX BENEFITS Unrecognized tax benefits represent potential future obligations to taxing authorities if uncertain tax positions we have taken on previously filed tax returns are not sustained. In accordance with our accounting policy, we accrue interest and penalties related to unrecognized tax benefits as a component of income tax expense (see Note 1: Summary of Significant Accounting Policies ). As of December 31, 2019, our 2016 and 2017 U.S. federal income tax returns are under examination. No foreign jurisdiction income tax returns are under examination. Our U.S. federal income tax returns are open to examination for years 2016 forward and foreign jurisdiction income tax returns are open to examination for years 2012 forward. We are undergoing examinations in state jurisdictions for tax years 2009 through 2017, with tax years 2009 forward open to examination. We do not expect that the outcome of any examination will have a material effect on our consolidated financial statements; however, audit outcomes and the timing of audit settlements are subject to significant uncertainty. RESOLUTION OF IRS MATTER In connection with the merger with Plum Creek, we acquired equity interests in Southern Diversified Timber, LLC (SDT), a timberland joint venture (Timberland Venture) with an affiliate of Campbell Global LLC (TCG Member). On August 31, 2016, the Timberland Venture redeemed TCG Member's interest and became a fully consolidated, wholly-owned subsidiary of Weyerhaeuser. We received a Notice of Final Partnership Administrative Adjustment (FPAA) dated July 20, 2016, from the Internal Revenue Service (IRS) in regard to Plum Creek's 2008 U.S. federal income tax treatment of the transaction forming the Timberland Venture. The IRS asserted that the transfer of the timberlands to the Timberland Venture was a taxable transaction to Plum Creek at the time of the transfer rather than a nontaxable capital contribution. We subsequently filed a petition in the U.S. Tax Court to contest this adjustment. On February 8, 2019, we entered into a closing agreement with the IRS to settle this dispute. Under the terms of the agreement, the company paid approximately $21 million of corporate tax. This amount was recorded as tax expense in fourth quarter 2018. No interest or penalties were assessed. The parties filed a stipulated decision with the U.S. Tax Court, pursuant to which the Court officially closed the matter.

GEOGRAPHIC AREAS

GEOGRAPHIC AREAS	12 Months Ended
	Dec. 31, 2019
Segments Geographical Areas [Abstract]
GEOGRAPHIC AREAS	NOTE 22: GEOGRAPHIC AREAS This note provides selected key financial data according to the geographical locations of our customers. SALES Our sales to unaffiliated customers outside the U.S. are primarily to customers in Canada, Japan and China. Our export sales are comprised primarily of logs, lumber and wood chips to Japan and China. Sales by Geographic Area DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Sales to unaffiliated customers: U.S. $ 5,674 $ 6,365 $ 6,168 Canada 440 519 472 Japan 305 410 352 China 90 120 107 Other foreign countries 45 62 97 Total $ 6,554 $ 7,476 $ 7,196 Export sales from the U.S.: Japan $ 265 $ 338 $ 295 China 85 113 102 Other foreign countries 129 153 148 Total $ 479 $ 604 $ 545 LONG-LIVED ASSETS Our long-lived assets used in the generation of revenues in different geographical areas are nearly all in the U.S. and Canada. Our long-lived assets primarily include: • property and equipment, including construction in progress, • timber and timberlands and • minerals and mineral rights. Long-Lived Assets by Geographic Area DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 U.S. $ 14,074 $ 14,778 Canada 275 220 Total $ 14,349 $ 14,998

SELECTED QUARTERLY FINANCIAL IN

SELECTED QUARTERLY FINANCIAL INFORMATION (unaudited)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
SELECTED QUARTERLY FINANCIAL INFORMATION (unaudited)	NOTE 23: SELECTED QUARTERLY FINANCIAL INFORMATION (UNAUDITED) Quarterly financial data provides a review of our results and performance throughout the year. Our earnings (loss) per share for the full year does not always equal the sum of the four quarterly earnings (loss) per share amounts because of common share activity during the year. As the company’s common shares are traded on the New York Stock Exchange (NYSE), market price information, such as the high and low trading prices for our common shares can be found under the symbol WY. Key Quarterly Financial Data DOLLAR AMOUNTS IN MILLIONS, EXCEPT PER-SHARE FIGURES FIRST QUARTER SECOND QUARTER THIRD QUARTER FOURTH QUARTER FULL YEAR 2019: Net sales $ 1,643 $ 1,692 $ 1,671 $ 1,548 $ 6,554 Operating income $ 174 $ 186 $ 202 $ 89 $ 651 Earnings (loss) before income taxes $ (393 ) $ 91 $ 102 $ (13 ) $ (213 ) Net earnings (loss) $ (289 ) $ 128 $ 99 $ (14 ) $ (76 ) Basic and diluted net earnings (loss) per share $ (0.39 ) $ 0.17 $ 0.13 $ (0.02 ) $ (0.10 ) Dividends paid per share $ 0.34 $ 0.34 $ 0.34 $ 0.34 $ 1.36 2018: Net sales $ 1,865 $ 2,065 $ 1,910 $ 1,636 $ 7,476 Operating income $ 404 $ 476 $ 337 $ 177 $ 1,394 Earnings (loss) before income taxes $ 299 $ 382 $ 240 $ (114 ) $ 807 Net earnings (loss) $ 269 $ 317 $ 255 $ (93 ) $ 748 Basic and diluted net earnings (loss) per share $ 0.35 $ 0.42 $ 0.34 $ (0.12 ) $ 0.99 Dividends paid per share $ 0.32 $ 0.32 $ 0.34 $ 0.34 $ 1.32

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Real Estate Investment Trust Election (REIT)	OUR ELECTION TO BE TAXED AS A REAL ESTATE INVESTMENT TRUST (REIT) Starting with our 2010 fiscal year, we elected to be taxed as a REIT. REIT income can be distributed to shareholders without first paying corporate level tax, substantially eliminating the double taxation on income. We expect to derive most of our REIT income from investments in timberlands, including the sale of standing timber through pay-as-cut sales contracts and lump sum timber deeds. We have not been subject to REIT built-in gains tax since December 31, 2014. We continue to be required to pay federal corporate income taxes on earnings of our Taxable REIT Subsidiaries (
Consolidated Financial Statements	Consolidated Financial Statements Our consolidated financial statements provide an overall view of our results and financial condition. They include our accounts and the accounts of entities that we control, including: • majority-owned domestic and foreign subsidiaries and • variable interest entities in which we are the primary beneficiary. They do not include our intercompany transactions and accounts, which are eliminated.
Our Business Segments	Our Business Segments Reportable business segments are determined based on the company’s "management approach," as defined by Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 280, Segment Reporting We are principally engaged in: • growing and harvesting timber; • manufacturing, distributing and selling products made from trees; • maximizing the value of every acre we own through the sale of higher and better use (HBU) properties and • monetizing the value of surface and subsurface assets through leases and royalties. Our business segments are organized based primarily on products and services. SEGMENT PRODUCTS AND SERVICES Timberlands Logs, timber, recreational leases and other products Real Estate & ENR Real Estate (sales of timberlands) and ENR (rights to explore for and extract hard minerals, construction materials, oil and gas production, wind and solar) Wood Products Structural lumber, oriented strand board, engineered wood products and building materials distribution We also transfer raw materials, semi-finished materials and end products among our business segments. Because of this intracompany activity, accounting for our business segments involves pricing products transferred between our business segments at current market values. Unallocated Items are gains or charges related to company level initiatives or previous businesses that are not allocated to our current business segments. They include all or a portion of items such as share-based compensation, pension and postretirement costs, elimination of intersegment profit in inventory and LIFO , foreign exchange transaction gains and losses , interest income and other as well as legacy obligations such as environmental remediation and workers compensation.
Estimates	Estimates We prepare our financial statements according to U.S. generally accepted accounting principles (U.S. GAAP). This requires us to make estimates and assumptions during our reporting periods and at the date of our financial statements. The estimates and assumptions affect our: • reported amounts of assets, liabilities and equity; • disclosure of contingent assets and liabilities and • reported amounts of revenues and expenses. While we do our best in preparing these estimates, actual results can and do differ from those estimates and assumptions.
Fair Value Measurements	Fair Value Measurements We use a fair value hierarchy in accounting for certain nonfinancial assets and liabilities including: • long-lived assets (asset groups) measured at fair value for an impairment assessment; • pension plan assets measured at fair value and • asset retirement obligations initially measured at fair value. The fair value hierarchy is based on inputs to valuation techniques that are used to measure fair value that are either observable or unobservable. Observable inputs reflect assumptions market participants would use in pricing an asset or liability based on market data obtained from independent sources while unobservable inputs reflect a reporting entity’s pricing based upon its own market assumptions. The fair value hierarchy consists of the following three levels: • Level 1: Inputs are unadjusted quoted prices for identical assets or liabilities traded in an active market. • Level 2: Inputs are quoted prices in non-active markets for which pricing inputs are observable either directly or indirectly at the reporting date. • Level 3: Inputs are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable.
Foreign Currency Translation	Foreign Currency Translation We translate foreign currencies into U.S. dollars in two ways: • assets and liabilities — at the exchange rates in effect as of our balance sheet date and • revenues and expenses — at average monthly exchange rates throughout the year.
Reclassifications	Reclassifications We have reclassified certain balances and results from prior years to be consistent with our 2019 reporting. This makes year-to-year comparisons easier. Our reclassifications had no effect on consolidated net earnings or equity.
New Accounting Pronouncements	New Accounting Pronouncements Lease Recognition On January 1, 2019 we adopted FASB ASC Topic 842, Leases With this adoption approach, financial information was not updated and disclosures required under the new standard were not provided for dates and periods before January 1, 2019. The adoption resulted in the recognition of additional right-of-use assets and lease liabilities for leases that each constitute less than 2 percent of total assets on our Consolidated Balance Sheet . These leases are primarily related to vehicles, equipment, office and warehouse locations as disclosed in Note 17: Leases . Benefit Plans Disclosure In August 2018, the FASB issued ASU 2018-14, which requires certain new disclosures, such as an explanation of the reasons for significant gains and losses related to changes in the benefit obligation for the period, as well as removes the requirement to disclose certain previously required information. The new guidance is effective retrospectively for all periods presented for fiscal periods starting after December 15, 2020, and early adoption is permitted. We adopted this ASU on December 31, 2019 and have updated our disclosures accordingly. This pronouncement does not have an effect on our consolidated financial statements. Refer to Note 9: Pension and Other Postretirement Benefit Plans
Property and Equipment	Property and Equipment We maintain property accounts on an individual asset basis and account for them as follows: • Improvements to and replacements of major units of property are capitalized. • Maintenance, repairs and minor replacements are expensed. • Depreciation is calculated using a straight-line method at rates based on estimated service lives. • Costs associated with logging roads that we intend to utilize for a period longer than one year are capitalized. These roads are then amortized over an estimated service life. • Cost and accumulated depreciation of property sold or retired are removed from the accounts and the gain or loss is included in earnings.
Timber and Timberlands	Timber and Timberlands We carry timber and timberlands at cost less depletion. Depletion refers to the carrying value of timber that is harvested, lost as a result of casualty or sold. Key activities affecting how we account for timber and timberlands include: • reforestation, • depletion and • forest management in Canada. Reforestation. Generally, we capitalize initial site preparation and planting costs as reforestation and then expense costs after the first planting as they are incurred or over the period of expected benefit. These expensed costs include: • fertilization, • vegetation and insect control, • pruning and precommercial thinning and • property taxes. Accounting practices for these costs do not change when timber becomes merchantable and harvesting starts. Timber depletion. To determine depletion rates, we divide the net carrying value of timber by the related volume of timber estimated to be available over the growth cycle. To determine the growth cycle volume of timber, we consider: • regulatory and environmental constraints, • our management strategies, • inventory data improvements, • growth rate revisions and recalibrations and • known dispositions and inoperable acres. In addition, the duration of the harvest cycle varies by geographic region and species of timber. Depletion rate calculations do not include estimates for: • future silviculture or sustainable forest management costs associated with existing stands; • future reforestation costs associated with a stand's final harvest and • future volume in connection with the replanting of a stand subsequent to its final harvest. We include the cost of timber harvested in the carrying values of raw materials and product inventories. As these inventories are sold to third parties, we include them in costs of sales. Forest Management in Canada. We manage timberlands under long-term licenses in various Canadian provinces that are: • granted by the provincial governments; • granted for initial periods of 15 to 25 years and • renewable provided we meet reforestation, operating and management guidelines. Calculation of the fees we pay on the timber we harvest: • varies from province to province, • is tied to product market pricing and • depends upon the allocation of land management responsibilities in the license.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets We review the carrying value of long-lived assets whenever an event or a change in circumstance indicates that the carrying value of the asset or asset group may not be recoverable through future operations. The carrying value is the original cost, less accumulated depreciation and any past impairments recorded. Impaired assets held for use are written down to fair value. Impaired assets held for sale are written down to fair value less cost to sell. We determine fair value based on: • appraisals, • market pricing of comparable assets, • discounted value of estimated future cash flows from the asset, • replacement values of comparable assets and • agreed upon sale price or offer price.
Financial Instruments	Financial Instruments We estimate the fair value of financial instruments where appropriate. The assumptions we use — including the discount rate and estimates of cash flows — can significantly affect our fair-value amounts. Our fair values are estimates and may not match the amounts we would realize upon sale or settlement of our financial positions.
Cash and Cash Equivalents and Accounts Payable	Cash Equivalents Cash equivalents are investments with maturities of 90 days or less at the date of purchase. We state cash equivalents at cost, which approximates market. Accounts Payable Our banking system replenishes our major bank accounts daily as checks we have issued are presented for payment. As a result, we may have negative book cash balances due to outstanding checks that have not yet been paid by the bank. These negative balances would be included in "Accounts payable" on our Consolidated Balance Sheet . Changes in these negative cash balances would be reported as financing activities on our Consolidated Statement of Cash Flows . We had no negative book cash balances as of December 31, 2019 or December 31, 2018
Concentration of Risk	Concentration of Risk We disclose customers that represent a concentration of risk. As of December 31, 2019, and December 31, 2018, no customer accounted for 10 percent or more of our net sales.
Revenue Recognition	Revenue Recognition Refer to Note 3: Revenue Recognition for detail on how we account for revenue. PERFORMANCE OBLIGATIONS A performance obligation, as defined in ASC Topic 606, is a promise in a contract to transfer a distinct good or service to a customer. A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue at the point in time, or over the period, in which the performance obligation is satisfied. Performance obligations associated with delivered log sales are typically satisfied when the logs are delivered to our customers’ mills or delivered to an ocean vessel in the case of export sales. Performance obligations associated with the sale of wood products are typically satisfied when the products are shipped. We have elected, as an accounting policy, to treat shipping and handling that is performed after a customer obtains control of the product as an activity required to fulfill the promise to transfer the good; therefore we will not evaluate this requirement as a separate performance obligation. Customers are generally invoiced shortly after logs are delivered or after wood products are shipped, with payment generally due within a month or less of the invoice date. ASC Topic 606 requires entities to consider significant financing components of contracts with customers, though allows for the use of a practical expedient when the period between satisfaction of a performance obligation and payment receipt is one year or less. Given the nature of our revenue transactions, we have elected to utilize this practical expedient. Performance obligations associated with real estate sales are generally met when placed into escrow and all conditions of closing have been satisfied. CONTRACT ESTIMATES Substantially all of our performance obligations are satisfied as of a point in time. Therefore, there is little judgment in determining when control transfers for our business segments as described above. The transaction price for log sales generally equals the amount billed to our customer for logs delivered during the accounting period. For the limited number of log sales subject to a long-term supply agreement, the transaction price is variable but is known at the time of billing. For wood products sales, the transaction price is generally the amount billed to the customer for the products shipped but may be reduced slightly for estimated cash discounts and rebates. There are no significant contract estimates related to the real estate business. CONTRACT BALANCES In general, customers are billed and a receivable is recorded as we ship and/or deliver wood products and logs. We generally receive payment shortly after products have been received by our customers. Contract asset and liability balances are immaterial. For real estate sales, the company receives the entire consideration in cash at closing.
Inventories	Inventories We state inventories at the lower of cost or net realizable value. Cost includes labor, materials and production overhead. LIFO — the last-in, first-out method — applies to major inventory products held at our U.S. domestic locations. We began to use the LIFO method for domestic products in the 1940s as required to conform with the tax method elected. Subsequent acquisitions of entities added new products under the FIFO — the first-in, first-out method — or moving average cost methods that have continued under those methods. The FIFO or moving average cost method applies to the balance of our domestic raw material and product inventories as well as for all material and supply inventories and all foreign inventories.
Shipping and Handling Costs	Shipping and Handling Costs We classify shipping and handling costs in "Costs of sales" on our Consolidated Statement of Operations .
Income Taxes	Income Taxes We account for income taxes under the asset and liability method. Unrecognized tax benefits represent potential future funding obligations to taxing authorities if uncertain tax positions we have taken on previously filed tax returns are not sustained. Accrued interest and penalties related to unrecognized tax benefits are recognized as a component of income tax expense. We recognize deferred tax assets and liabilities to reflect: • future tax consequences due to differences between the carrying amounts for financial reporting purposes and the tax bases of certain items and • net operating loss and tax credit carryforwards. To measure deferred tax assets and liabilities, we: • determine when the differences between the carrying amounts and tax bases of affected items are expected to be recovered or resolved and • use enacted tax rates expected to apply to taxable income in those years.
Pension and Other Postretirement Benefit Plans	Pension and Other Postretirement Benefit Plans We recognize the overfunded or underfunded status of our defined benefit pension and other postretirement plans on our Consolidated Balance Sheet and recognize changes in the funded status through comprehensive income (loss) in the year in which the changes occur. Actuarial valuations determine the amount of the pension and other postretirement benefit obligations and the net periodic benefit cost we recognize. The net periodic benefit cost includes: • cost of benefits provided in exchange for employees’ services rendered during the year; • interest cost of the obligations; • expected long-term return on plan assets; • gains or losses on plan settlements and curtailments; • amortization of prior service costs and plan amendments over the average remaining service period of the active employee group covered by the plans or the average remaining life expectancy in situations where the plan participants affected by the plan amendment are inactive and • amortization of cumulative unrecognized net actuarial gains and losses — generally in excess of 10 percent of the greater of the benefit obligation or the combination of market-related and fair value of plan assets at the beginning of the year — over the average remaining service period of the active employee group covered by the plans or the average remaining life expectancy in situations where the plan participants are inactive. Pension plans. We have defined benefit pension plans covering approximately half of our employees. Determination of benefits differs for salaried, hourly and union employees as follows: • Salaried employee benefits are based on each employee’s highest monthly earnings for five consecutive years during the final 10 years before retirement. • Hourly and union employee benefits generally are stated amounts for each year of service. • Union employee benefits are set through collective-bargaining agreements. We contribute to our U.S. and Canadian pension plans according to established funding standards. The funding standards for the plans are: • U.S. pension plans — according to the Employee Retirement Income Security Act of 1974 and • Canadian pension plans — according to the applicable provincial pension act and the Income Tax Act. Postretirement benefits other than pensions. We provide certain postretirement health care and life insurance benefits for some retired employees. In some cases, we pay a portion of the cost of the benefit. Note 9: Pension and Other Postretirement Benefit Plans provides additional information about our postretirement benefit plans.
Environmental Remediation	Environmental Remediation We accrue losses associated with environmental remediation obligations when such losses are probable and reasonably estimable. Future expenditures for environmental remediation obligations are not discounted to their present value. Recoveries of environmental remediation costs from other parties are recorded as assets when the recovery is deemed probable and does not exceed the amount of losses previously recorded.
Earnings Per Share	Basic earnings (loss) per share is net earnings (loss) available to common shareholders divided by the weighted average number of our outstanding common shares, including stock equivalent units where there is no circumstance under which those shares would not be issued. Diluted earnings (loss) per share is net earnings (loss) available to common shareholders divided by the sum of the: • weighted average number of our outstanding common shares and • the effect of our outstanding dilutive potential common shares. Dilutive potential common shares may include: • outstanding stock options, • restricted stock units and • performance share units. We use the treasury stock method to calculate the dilutive effect of our outstanding stock options, restricted stock units and performance share units. Share-based payment awards that are contingently issuable upon the achievement of specified performance or market conditions are included in our diluted earnings per share calculation in the period in which the conditions are satisfied.
Stock Repurchase Programs Policy	All common stock repurchases under the 2016 and 2019 Repurchase Programs were made in open-market transactions.
Share-based Compensation	HOW WE ACCOUNT FOR SHARE-BASED AWARDS When accounting for share-based awards we: • use a fair-value-based measurement and • recognize the cost of share-based awards on our consolidated financial statements. We recognize the cost of share-based awards on our Consolidated Statement of Operations over the required service period — generally the period from the date of the grant to the date when it is fully vested. Special situations include: • Awards that vest upon retirement — the required service period ends on the date an employee is eligible for retirement, including early retirement. • Awards that continue to vest following job elimination or the sale of a business — the required service period ends on the date the employment from the company is terminated. In these special situations, compensation expense from share-based awards is recognized over a period that is shorter than the stated vesting period.

BUSINESS SEGMENTS (Tables)

BUSINESS SEGMENTS (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Sales and Net Contribution (Charge) to Earnings	Sales and Net Contribution (Charge) to Earnings DOLLAR AMOUNTS IN MILLIONS TIMBERLANDS REAL ESTATE & ENR WOOD PRODUCTS UNALLOCATED ITEMS AND INTERSEGMENT ELIMINATIONS CONSOLIDATED Sales to unaffiliated customers (1) 2019 $ 1,618 $ 313 $ 4,623 $ — $ 6,554 2018 $ 1,873 $ 306 $ 5,297 $ — $ 7,476 2017 $ 1,893 $ 280 $ 5,023 $ — $ 7,196 Intersegment sales (1) 2019 $ 503 $ 1 $ — $ (504 ) $ — 2018 $ 537 $ 1 $ — $ (538 ) $ — 2017 $ 522 $ 1 $ — $ (523 ) $ — Net contribution (charge) to earnings 2019 $ 347 $ 144 $ 353 $ (679 ) $ 165 2018 $ 583 $ 127 $ 838 $ (366 ) $ 1,182 2017 $ 532 $ 146 $ 569 $ (138 ) $ 1,109 (1) In 2019, we changed the way we report our Canadian Forestlands operations. As a result, we no longer report related intersegment sales in the Timberlands segment and we now record the minimal associated third-party log sales in the Wood Products segment. These collective transactions did not contribute any earnings to the Timberlands or Wood Products segment. We have conformed prior year presentations with the current year.
Reconciliation of Net Contribution to Earnings to Net Earnings (Loss)	Reconciliation of Net Contribution to Earnings to Net Earnings (Loss) DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Net contribution to earnings $ 165 $ 1,182 $ 1,109 Interest expense, net of capitalized interest (378 ) (375 ) (393 ) Income (loss) before income taxes (213 ) 807 716 Income taxes 137 (59 ) (134 ) Net earnings (loss) $ (76 ) $ 748 $ 582
Additional Financial Information	Additional Financial Information DOLLAR AMOUNTS IN MILLIONS TIMBERLANDS REAL ESTATE & ENR WOOD PRODUCTS UNALLOCATED ITEMS CONSOLIDATED Depreciation, depletion and amortization 2019 $ 301 $ 14 $ 191 $ 4 $ 510 2018 $ 319 $ 14 $ 149 $ 4 $ 486 2017 $ 356 $ 15 $ 145 $ 5 $ 521 Capital expenditures 2019 $ 112 $ — $ 257 $ 15 $ 384 2018 $ 117 $ — $ 306 $ 4 $ 427 2017 $ 115 $ 2 $ 299 $ 3 $ 419
Total Assets	Total Assets DOLLAR AMOUNTS IN MILLIONS TIMBERLANDS and REAL ESTATE & ENR WOOD PRODUCTS UNALLOCATED ITEMS CONSOLIDATED Total assets (1)(2) 2019 $ 13,130 $ 2,452 $ 824 $ 16,406 2018 $ 13,792 $ 2,280 $ 1,177 $ 17,249 (1) In 2019, we changed the way we report our Canadian Forestlands operations. As a result, Canadian Forestlands assets previously reported in the Timberlands segment are now recorded in the Wood Products segment. We have conformed prior year presentations with the current year. (2) Assets attributable to the Real Estate & ENR business segment are combined with total assets for the Timberlands segment as we do not produce separate balance sheets internally.

REVENUE RECOGNITION (Tables)

REVENUE RECOGNITION (Tables)	12 Months Ended
	Dec. 31, 2019
Revenue From Contract With Customer [Abstract]
Revenue by Major Products	A Reconciliation of Revenue Recognized by our Major Products: DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Net sales to unaffiliated customers: Timberlands segment (1) Delivered logs: West Domestic sales $ 375 $ 503 $ 473 Export grade sales 365 484 442 Subtotal West 740 987 915 South 640 625 616 North (2) 92 99 95 Other (3) — — 23 Subtotal delivered logs sales 1,472 1,711 1,649 Stumpage and pay-as-cut timber 42 59 73 Recreational and other lease revenue 61 59 59 Other (4) 43 44 112 Net sales attributable to Timberlands segment 1,618 1,873 1,893 Real Estate & ENR segment Real estate 225 229 208 Energy and natural resources 88 77 72 Net sales attributable to Real Estate & ENR segment 313 306 280 Wood Products segment (1) Structural lumber 1,892 2,258 2,058 Oriented strand board 632 891 904 Engineered solid section 510 521 500 Engineered I-joists 323 336 336 Softwood plywood 161 200 176 Medium density fiberboard 166 177 183 Complementary building products 602 584 541 Other (5) 337 330 325 Net sales attributable to Wood Products segment 4,623 5,297 5,023 Total $ 6,554 $ 7,476 $ 7,196 (1 ) In 2019, we changed the way we report our Canadian Forestlands operations. As a result, we no longer report related intersegment sales in the Timberlands segment and we now record the minimal associated third-party log sales in the Wood Products segment. These collective transactions did not contribute any earnings to the Timberlands or Wood Products segment. We have conformed prior year presentations with the current year. (2) In November 2019, we sold our Michigan timberlands. Refer to Note 4: Divestitures and Assets Held for Sale for further information on this divestiture. (3) Other delivered logs included sales from timberlands managed for the Twin Creeks Venture. Our management agreement for the Twin Creeks Venture began in April 2016 and terminated in December 2017. For additional information see Note 8: Related Parties . ( 4 ) Other Timberlands sales includes sales of seeds and seedlings from our nursery operations as well as wood chips. Prior to our Uruguay operations being divested in September 2017, sales from these operations were included within this amount as well. Refer to Note 4: Divestitures and Assets Held for Sale for further information on this divestiture. ( 5 ) Other Wood Products sales include wood chips, other byproducts and third-party residual log sales from our Canadian Forestlands operations.

NET EARNINGS (LOSS) PER SHARE (

NET EARNINGS (LOSS) PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Earnings (Loss) per Share	Calculation of Weighted Average Number of Outstanding Common Shares – Dilutive SHARES IN THOUSANDS 2019 2018 2017 Weighted average number of outstanding shares - basic 745,897 754,556 753,085 Dilutive potential common shares: Stock options — 1,310 2,571 Restricted stock units — 566 582 Performance share units — 395 428 Total effect of outstanding dilutive potential common shares — 2,271 3,581 Weighted average number of outstanding common shares - dilutive 745,897 756,827 756,666
Potential Shares Not Included in the Computation of Diluted Earnings (Loss) per Share	Potential Shares Not Included in the Computation of Diluted Earnings (Loss) per Share SHARES IN THOUSANDS 2019 2018 2017 Stock options 2,631 2,402 1,351 Restricted stock units 477 — — Performance share units 1,131 1,080 799

INVENTORIES (Tables)

INVENTORIES (Tables)	12 Months Ended
	Dec. 31, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories include raw materials, work-in-process, finished goods as well as materials and supplies, as shown below: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 LIFO inventories: Logs $ 19 $ 11 Lumber, plywood, panels and fiberboard 82 75 Other products 10 10 FIFO or moving average cost inventories: Logs 28 35 Lumber, plywood, panels, fiberboard and engineered wood products 84 86 Other products 98 83 Materials and supplies 95 89 Total $ 416 $ 389

PROPERTY AND EQUIPMENT (Tables)

PROPERTY AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2019
Property Plant And Equipment [Abstract]
Carrying Value of Property and Equipment and Estimated Service Lives	Carrying Value of Property and Equipment and Estimated Service Lives DOLLAR AMOUNTS IN MILLIONS RANGE OF LIVES DECEMBER 31, 2019 DECEMBER 31, 2018 Property and equipment, at cost: Land N/A $ 87 $ 87 Buildings and improvements 15-40 999 942 Machinery and equipment 5-25 3,425 3,240 Roads 10-35 742 785 Other 3-10 193 179 Total cost 5,446 5,233 Accumulated depreciation and amortization (3,477 ) (3,376 ) Property and equipment, net $ 1,969 $ 1,857

PENSION AND OTHER POSTRETIREM_2

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Tables)	12 Months Ended
	Dec. 31, 2019
Funded Status of Our Plans	The funded status of the plans we sponsor is determined by comparing the projected benefit obligation with the fair value of plan assets at the end of the year. The following table demonstrates how our plans' funded status is reflected on the Consolidated Balance Sheet . DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2019 2018 Funded status: Fair value of plan assets (1) $ 3,719 $ 4,930 $ 19 $ 18 Projected benefit obligations (4,260 ) (5,263 ) (151 ) (166 ) Funded status (541 ) (333 ) (132 ) (148 ) Presentation on our Consolidated Balance Sheet Noncurrent assets $ 47 $ 74 $ — $ — Current liabilities (19 ) (18 ) (8 ) (10 ) Noncurrent liabilities (569 ) (389 ) (124 ) (138 ) Funded status $ (541 ) $ (333 ) $ (132 ) $ (148 ) (1) Fair value of plan assets as of December 31, 2018 includes amounts associated with the $300 million voluntary contribution made during 2018 in anticipation of our 2018 term-vested lump sum and 2019 retiree annuity purchase transactions. Refer to the “Actions to Reduce Pension Plan Obligations” section for further details of this contribution and the related transactions.
Changes in Fair Value of Plan Assets	Changes in Fair Value of Plan Assets DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2019 2018 Fair value of plan assets at beginning of year (estimated) $ 4,930 $ 5,514 $ 18 $ — Adjustment for final fair value of plan assets 16 44 — — Actual return on plan assets 449 123 1 — Foreign currency translation 38 (73 ) — — Employer contributions and benefit payments 30 345 15 36 Plan participants’ contributions — — 2 4 Plan transfers 1 1 — — Benefits paid (includes lump sum and annuity transfers) (1,745 ) (1,024 ) (17 ) (22 ) Fair value of plan assets at end of year (estimated) $ 3,719 $ 4,930 $ 19 $ 18
Changes in Projected Benefit Obligations of Our Pension and Other Postretirement Benefit Plans	Changes in Projected Benefit Obligations of Our Pension and Other Postretirement Benefit Plans DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2019 2018 Projected benefit obligation beginning of year $ 5,263 $ 6,795 $ 166 $ 200 Service cost 32 37 — — Interest cost 160 236 6 7 Plan participants’ contributions — — 2 4 Actuarial (gains) losses 510 (718 ) (8 ) (18 ) Foreign currency translation 39 (69 ) 2 (5 ) Benefits paid (includes lump sum and annuity transfers) (1,745 ) (1,024 ) (17 ) (22 ) Plan amendments and other — 5 — — Plan transfers 1 1 — — Projected benefit obligation at end of year $ 4,260 $ 5,263 $ 151 $ 166
Schedules of Allocation of Our Plans' Assets	The net pension plan assets, when categorized in accordance with this fair value hierarchy, are as follows. Investments valued using NAV as a practical expedient are presented to reconcile with total plan assets. DOLLAR AMOUNTS IN MILLIONS 2019 LEVEL 1 LEVEL 2 LEVEL 3 NAV TOTAL Pension trust investments: Cash and short-term investments $ 120 $ — $ — $ — $ 120 Fixed income investments: Corporate — 1,260 — — 1,260 Government — 941 — — 941 Repurchase agreements — (176 ) — — (176 ) Public equity investments 4 — — — 4 Hedge fund and related investments — — 13 518 531 Private equity and related investments — — 86 942 1,028 Derivative instruments — 10 — — 10 Total pension trust investments 124 2,035 99 1,460 3,718 Accrued liabilities, net (9 ) Pension trust net assets 3,709 Canadian nonregistered plan assets: Cash and short-term investments 5 — — — 5 Public equity investments 5 — — — 5 Total Canadian nonregistered plan assets 10 — — — 10 Total plan assets $ 3,719 DOLLAR AMOUNTS IN MILLIONS 2018 LEVEL 1 LEVEL 2 LEVEL 3 NAV TOTAL Pension trust investments: Cash and short-term investments $ 275 $ 12 $ — $ — $ 287 Fixed income investments: Corporate — 1,054 — — 1,054 Government — 426 — — 426 Hedge fund and related investments — — 3 1,811 1,814 Private equity and related investments — — 65 1,014 1,079 Derivative instruments — 15 262 — 277 Total pension trust investments 275 1,507 330 2,825 4,937 Accrued liabilities, net (17 ) Pension trust net assets 4,920 Canadian nonregistered plan assets: Cash and short-term investments 5 — — — 5 Public equity investments 5 — — — 5 Total Canadian nonregistered plan assets 10 — — — 10 Total plan assets $ 4,930
Reconciliation of Pension Plan Assets Measured at Level 3 Fair Value	A reconciliation of the beginning and ending balances of the pension plan assets measured at fair value using significant unobservable inputs (Level 3) is presented below: DOLLAR AMOUNTS IN MILLIONS INVESTMENTS Hedge funds and related investments Private equity and related investments Derivative instruments, net Total Balance as of December 31, 2017 $ 10 $ 102 $ 445 $ 557 Net realized gains (losses) — — 238 238 Net change in unrealized gains (losses) 1 (5 ) (184 ) (188 ) Purchases — 5 — 5 Sales — (2 ) — (2 ) Settlements — — (237 ) (237 ) Transfers into Level 3 — 18 — 18 Transfers out of Level 3 (8 ) (53 ) — (61 ) Balance as of December 31, 2018 3 65 262 330 Net realized gains (losses) 1 (1 ) 237 237 Net change in unrealized gains (losses) (1 ) — (262 ) (263 ) Purchases — — — — Sales (3 ) (3 ) — (6 ) Settlements — — (237 ) (237 ) Transfers into Level 3 13 28 — 41 Transfers out of Level 3 — (3 ) — (3 ) Balance as of December 31, 2019 $ 13 $ 86 $ — $ 99
Assumptions We Use in Estimating Health Care Benefit Costs	Assumptions We Use in Estimating Health Care Benefit Obligations 2019 2018 U.S. CANADA U.S. CANADA Weighted health care cost trend rate assumed for next year 7.30% for Pre- Medicare and 4.50% for HRA 5.40% 7.80% for Pre- Medicare and 4.50% for HRA 4.90% Rate that the cost trend rate gradually declines to 4.50% 4.00% 4.50% 4.00% Year the cost trend rate is reached 2037 2039 2037 2039
Net Periodic Benefit Cost (Credit)	Net Periodic Benefit Cost (Credit) DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2019 2018 2017 2019 2018 2017 Net periodic benefit cost (credit): Service cost $ 32 $ 37 $ 35 $ — $ — $ — Interest cost 160 236 264 6 7 8 Expected return on plan assets (223 ) (399 ) (409 ) — — — Amortization of actuarial loss 112 225 195 7 8 8 Amortization of prior service cost (credit) 4 3 4 (5 ) (8 ) (8 ) Settlement charges 455 200 — — — — Net periodic benefit cost (credit) $ 540 $ 302 $ 89 $ 8 $ 7 $ 8
Estimated Projected Benefit Payments for the Next 10 Years	Estimated Projected Benefit Payments for the Next 10 Years DOLLAR AMOUNTS IN MILLIONS PENSION OTHER POSTRETIREMENT BENEFITS 2020 $ 237 $ 14 2021 $ 235 $ 13 2022 $ 236 $ 13 2023 $ 238 $ 12 2024 $ 237 $ 11 2025-2029 $ 1,176 $ 47
Pension
Rates We Use in Estimating Our Benefit Obligations	Rates We Use in Estimating Our Benefit Obligations PENSION DECEMBER 31, 2019 DECEMBER 31, 2018 Discount rates: United States 3.40% 4.40% Canada 3.10% 3.70% Lump sum distributions (1)(2) PPA Table PPA Table Rate of compensation increase: Salaried: United States 13.00% to 2.00% decreasing with participant age 13.00% to 2.00% decreasing with participant age Canada 3.25% 3.25% Hourly: United States 13.00% to 2.30% decreasing with participant age 13.00% to 2.30% decreasing with participant age Canada 3.00% 3.00% Lump sum or installment distributions election (2) 60.00% 60.00% (1) PPA Phased Table: Interest and mortality assumptions as mandated by Pension Protection Act of 2006. (2) U.S. qualified salaried and nonqualified plans only.
Estimating Our Net Periodic Benefit Costs	Estimating Our Net Periodic Benefit Costs PENSION 2019 2018 2017 Discount rates: United States (1) 4.30% 3.70% 4.30% Canada 3.70% 3.50% 3.70% Lump sum distributions (2)(3) PPA Table PPA Table PPA Table Expected return on plan assets: Qualified/registered plans 7.00% 8.00% 8.00% Rate of compensation increase: Salaried: United States 13.00% to 2.00% decreasing with participant age 13.00% to 2.00% decreasing with participant age 13.00% to 2.00% decreasing with participant age Canada 3.25% 3.25% 3.50% Hourly: United States 13.00% to 2.30% decreasing with participant age 13.00% to 2.30% decreasing with participant age 13.00% to 2.30% decreasing with participant age Canada 3.00% 3.00% 3.25% Lump sum distributions election (3) 60.00% 60.00% 60.00% (1) In January 2019, we transferred approximately $1.5 billion of U.S. qualified pension plan assets and liabilities to an insurance company through the purchase of a group annuity contract. The settlement of this liability triggered a plan remeasurement, which caused a change in our 2019 pension plan discount rate. The initial discount rate used to estimate our net periodic benefit costs from January 1, 2019 through January 31, 2019 was 4.40 percent. As a result of the remeasurement, the discount rate was updated to 4.30 percent for the remainder of 2019. Refer to the “Actions to Reduce Pension Plan Obligations” section above for more details of this transaction. ( 2 ) PPA Phased Table: Interest and mortality assumptions as mandated by Pension Protection Act of 2006. ( 3 ) U.S. qualified salaried and nonqualified plans only.
Qualified and Registered Plans
Schedules of Allocation of Our Plans' Assets	Assets within our qualified and registered pension plans in our U.S. and Canadian pension trusts were invested as follows: DECEMBER 31, 2019 DECEMBER 31, 2018 Cash and short-term investments 3.2% 5.8% Fixed income investments: Corporate 33.9 21.5 Government 25.4 8.6 Repurchase agreements (4.7 ) — Public equity investments 0.1 — Hedge funds and related investments 14.3 36.9 Private equity and related investments 27.7 21.9 Derivative instruments, net 0.3 5.6 Accrued liabilities (0.2 ) (0.3 ) Total 100.0% 100.0%
Qualified and Registered Plans | Derivative instruments
Schedules of Allocation of Our Plans' Assets	The table below shows the fair value and aggregate notional amount of the derivative instruments held by our pension trusts at the end of the last two years. DOLLAR AMOUNTS IN MILLIONS FAIR VALUE NOTIONAL DECEMBER 31, 2019 DECEMBER 31, 2018 DECEMBER 31, 2019 DECEMBER 31, 2018 Foreign currency derivatives, net $ — $ — $ — $ 13 Futures contracts, net 10 15 813 1,073 Total return swaps, net — 262 — 558 Total $ 10 $ 277 $ 813 $ 1,644

ACCRUED LIABILITIES (Tables)

ACCRUED LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2019
Accrued Liabilities Current [Abstract]
Accrued Liabilities	Accrued liabilities were comprised of the following: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Compensation and employee benefit costs $ 188 $ 192 Current portion of lease liabilities ( Note 17 ) 33 — Customer rebates, volume discounts and deferred income 105 99 Interest 98 109 Taxes payable 24 30 Other 82 60 Total $ 530 $ 490

LINES OF CREDIT (Tables)

LINES OF CREDIT (Tables)	12 Months Ended
	Dec. 31, 2019
Short Term Debt Other Disclosures [Abstract]
Letters of Credit and Surety Bonds	LETTERS OF CREDIT AND SURETY BONDS The amounts of letters of credit and surety bonds we have entered into as of the end of the last two years are included in the following table: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Letters of credit $ 35 $ 38 Surety bonds $ 127 $ 123

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Long-Term Debt by Types and Interest Rates (Includes Current Portion)	The following table lists our long-term debt by types and interest rates at the end of our last two years and includes the current portion. Long-Term Debt by Types and Interest Rates (Includes Current Portion) DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 7.375% notes due 2019 $ — $ 500 9.00% debentures due 2021 150 150 4.70% debentures due 2021 569 569 7.125% debentures due 2023 191 191 5.207% debentures due 2023 860 860 4.625% notes due 2023 500 500 3.25% debentures due 2023 325 325 8.50% debentures due 2025 300 300 7.95% debentures due 2025 136 136 7.70% debentures due 2026 150 150 7.35% debentures due 2026 62 62 7.85% debentures due 2026 100 100 Variable-rate term loan credit facility matures 2026 225 225 6.95% debentures due 2027 300 300 4.00% notes due 2029 750 — 7.375% debentures due 2032 1,250 1,250 6.875% debentures due 2033 275 275 Other 1 1 Total principal long-term debt 6,144 5,894 Add: fair value adjustments (related to Plum Creek merger) 27 39 Less: unamortized discounts (14 ) (5 ) Less: unamortized debt expense (10 ) (9 ) Total $ 6,147 $ 5,919 Portion due within one year $ — $ 500
Amounts of Long-Term Debt Due Annually for the Next Five Years and Thereafter	Amounts of Long-Term Debt Due Annually for the Next Five Years and Thereafter DOLLAR AMOUNTS IN MILLIONS (1) 2020 $ — 2021 $ 719 2022 $ — 2023 $ 1,876 2024 $ — Thereafter $ 3,549 (1) Excludes $3 million of unamortized discounts, capitalized debt expense and fair value adjustments (related to Plum Creek merger).

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Abstract]
Estimated Fair Values and Carrying Values of Long-Term Debt and Line of Credit	The estimated fair values and carrying values of our long-term debt and line of credit consisted of the following: DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 CARRYING VALUE FAIR VALUE (LEVEL 2) CARRYING VALUE FAIR VALUE (LEVEL 2) Long-term debt (including current maturities) and line of credit: Fixed rate $ 5,922 $ 6,986 $ 5,694 $ 6,345 Variable rate 455 455 650 650 Total Debt $ 6,377 $ 7,441 $ 6,344 $ 6,995

LEGAL PROCEEDINGS, COMMITMENT_2

LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Changes in the Reserve for Environmental Remediation	Changes in the Reserve for Environmental Remediation DOLLAR AMOUNTS IN MILLIONS Reserve balance as of December 31, 2018 $ 62 Reserve charges and adjustments, net 4 Payments (5 ) Reserve balance as of December 31, 2019 $ 61

SHAREHOLDERS' INTEREST (Tables)

SHAREHOLDERS' INTEREST (Tables)	12 Months Ended
	Dec. 31, 2019
Stockholders Equity Note [Abstract]
Reconciliation of Our Common Share Activity	Reconciliation of Our Common Share Activity SHARES IN THOUSANDS 2019 2018 2017 Outstanding at beginning of year 746,391 755,223 748,528 Stock options exercised 660 2,026 5,970 Issued for vested restricted stock units 480 466 605 Issued for vested performance share units 118 86 120 Repurchased (2,349 ) (11,410 ) — Outstanding at end of year 745,300 746,391 755,223
Changes in Amounts Included in Our Accumulated Other Comprehensive Loss	Changes in amounts included in our accumulated other comprehensive loss by component are: DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Pension (1) Balance at beginning of period $ (1,343 ) $ (1,810 ) $ (1,660 ) Other comprehensive income (loss) before reclassifications (216 ) 388 (282 ) Amounts reclassified from accumulated other comprehensive income (loss) to earnings (2)(3) 431 325 132 Total other comprehensive income (loss) 215 713 (150 ) Reclassification of certain effects due to tax law changes (4) — (246 ) — Balance at end of period (1,128 ) (1,343 ) (1,810 ) Other Postretirement Benefits (1) Balance at beginning of period (19 ) (25 ) (38 ) Other comprehensive income (loss) before reclassifications 6 13 14 Amounts reclassified from accumulated other comprehensive income (loss) to earnings (2) 1 — (1 ) Total other comprehensive income (loss) 7 13 13 Reclassification of certain tax effects due to tax law changes (4) — (7 ) — Balance at end of period (12 ) (19 ) (25 ) Translation Adjustments and Other Balance at beginning of period 210 273 239 Translation adjustments 26 (54 ) 34 Total other comprehensive income (loss) 26 (54 ) 34 Reclassification of accumulated unrealized gains on available-for-sale securities (5) — (9 ) — Balance at end of period 236 210 273 Accumulated other comprehensive loss, end of period $ (904 ) $ (1,152 ) $ (1,562 ) (1) Amounts are presented net of tax. (2) Amounts of actuarial loss and prior service (cost) credit are components of net periodic benefit cost (credit). See Note 9: Pension and Other Postretirement Benefit Plans . (3) Amounts include settlement charges totaling $455 million and $200 million related to our pension plans for the years ended December 31, 2019 and December 31, 2018, respectively. See Note 9: Pension and Other Postretirement Benefit Plans for further detail. (4) During 2018, we reclassified certain tax effects from tax law changes of $253 million from "Accumulated other comprehensive loss" to "Retained earnings" on our Consolidated Balance Sheet in accordance with ASU 2018-02. (5) During 2018, we reclassified accumulated unrealized gains on available-for-sale securities of $9 million from "Accumulated other comprehensive loss" to "Retained earnings" on our Consolidated Balance Sheet in accordance with ASU 2016-01.

SHARE-BASED COMPENSATION (Table

SHARE-BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 31, 2019
Share Based Compensation [Abstract]
Schedule of Restricted Stock Units Activity	Activity The following table shows our RSU activity for 2019: RESTRICTED STOCK UNITS (IN THOUSANDS) WEIGHTED AVERAGE GRANT-DATE FAIR VALUE Nonvested at December 31, 2018 1,593 $ 31.41 Granted 865 $ 25.83 Vested (582 ) $ 30.34 Forfeited (87 ) $ 29.40 Nonvested at December 31, 2019 (1) 1,789 $ 29.15 ( 1) As of December 31, 2019, there were approximately 526 thousand RSUs that had met the requisite service period and will be released as identified in the grant terms.
Weighted Average Assumptions Used in Estimating the Value of Performance Share Units	Weighted Average Assumptions Used in Estimating the Value of PSUs 2019 GRANTS 2018 GRANTS 2017 GRANTS Performance period 1/1/2019-12/31/2021 1/1/2018-12/31/2020 1/1/2017-12/31/2019 Expected dividends 5.25% 3.81% 3.74% Risk-free rate 2.43% - 2.55% 1.75% - 2.34% 0.68% - 1.55% Volatility 22.50% - 27.40% 17.30% - 21.52% 22.71% - 24.07% Weighted average grant-date fair value $ 29.66 $ 35.49 $ 37.93
Schedule of Performance Share Units Activity	Activity The following table shows our PSU activity for 2019: GRANTS (IN THOUSANDS) WEIGHTED AVERAGE GRANT-DATE FAIR VALUE Nonvested at December 31, 2018 1,042 $ 31.52 Granted at target 419 29.66 Vested (153 ) 22.80 Forfeited (26 ) 34.05 Performance adjustment (233 ) 22.80 Nonvested at December 31, 2019 (1) 1,049 $ 33.93 (1) As of December 31, 2019, there were approximately 519 thousand PSUs that had met the requisite service period and will be released as identified in the grant terms.
Schedule of Stock Options Activity	Activity The following table shows our stock option activity for 2019: OPTIONS (IN THOUSANDS) WEIGHTED AVERAGE EXERCISE PRICE WEIGHTED AVERAGE REMAINING CONTRACTUAL TERM (IN YEARS) AGGREGATE INTRINSIC VALUE (IN MILLIONS) Outstanding at December 31, 2018 6,366 $ 26.75 Exercised (661 ) $ 19.16 Forfeited or expired (430 ) $ 31.63 Outstanding at December 31, 2019 (1) 5,275 $ 27.30 4.61 $ 21 Exercisable at December 31, 2019 4,678 $ 27.84 4.42 $ 17 (1) As of December 31, 2019, there were approximately 324 thousand stock options that had met the requisite service period and will be released as identified in the grant terms.

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Lease Expense	Lease Expense DOLLAR AMOUNTS IN MILLIONS 2019 Operating lease costs $ 20 Financing lease costs 15 Total lease costs $ 35
Supplemental Cash Flow Information	Supplemental Cash Flow Information DOLLAR AMOUNTS IN MILLIONS 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 20 Financing cash flows for financing leases (1) $ 16 ROU assets obtained in exchange for new (modified) lease liabilities: Operating leases $ 6 Financing leases $ 5 (1) Interest expense related to financing leases was immaterial during 2019.
Supplemental Balance Sheet Information Related to Leases	Supplemental Balance Sheet Information Related to Leases DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 LEASES BALANCE SHEET CLASSIFICATION Assets Operating lease ROU assets Other assets $ 120 Financing lease ROU assets Property and equipment, net 28 Total leased assets $ 148 Liabilities Current: Operating lease liabilities Accrued liabilities $ 20 Financing lease liabilities Accrued liabilities 13 Noncurrent: Operating lease liabilities Other liabilities 103 Financing lease liabilities Other liabilities 20 Total lease liabilities $ 156
Weighted Average Remaining Lease Term	Weighted Average Remaining Lease Term DECEMBER 31, 2019 Operating leases 11 years Financing leases 3 years Weighted Average Discount Rate DECEMBER 31, 2019 Operating leases 4.2% Financing leases 3.1%
Schedule of Maturities of Operating and Finance Leases Liabilities	Maturities of Lease Liabilities as of December 31, 2019 DOLLAR AMOUNTS IN MILLIONS OPERATING LEASES FINANCING LEASES 2020 $ 20 $ 14 2021 18 10 2022 17 7 2023 16 4 2024 12 — Thereafter 70 — Total lease payments 153 35 Less: interest (30 ) (2 ) Total present value of lease liabilities $ 123 $ 33
Schedule of Operating Lease Commitments	Operating Lease Commitments as of December 31, 2018 DOLLAR AMOUNTS IN MILLIONS 2019 $ 35 2020 $ 29 2021 $ 26 2022 $ 24 2023 $ 18 Thereafter $ 78

OTHER OPERATING COSTS (INCOME_2

OTHER OPERATING COSTS (INCOME), NET (Tables)	12 Months Ended
	Dec. 31, 2019
Other Income [Abstract]
Income and Expense Items Included in Other Operating Costs (Income), Net	Income and Expense Items Included in Other Operating Costs (Income), Net DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Environmental remediation insurance recoveries $ — $ (5 ) $ (42 ) Foreign exchange losses (gains), net (1) 2 (3 ) (1 ) Gain on disposition of nonstrategic assets (4 ) (5 ) (16 ) Gain on sale of timberlands (2) (48 ) — (99 ) Litigation expense, net 63 35 20 Research and development expenses 6 8 14 Other, net (3) 28 52 10 Total other operating costs (income), net $ 47 $ 82 $ (114 ) (1) Foreign exchange gains and losses result from changes in exchange rates primarily related to our U.S. dollar denominated cash and debt balances that are held by our Canadian subsidiary. (2) The 2019 gain on sale of timberlands relates to the sale of our Michigan timberlands during fourth quarter 2019. The 2017 amount relates to 100,000 acres sold to Twin Creeks during fourth quarter 2017. Refer to Note 4: Divestitures and Assets Held for Sale Note 8: Related Parties (3) "Other, net" includes environmental remediation charges. See Note 14: Legal Proceedings, Commitments and Contingencies for more information.

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Domestic and Foreign Earnings (Loss) Before Income Taxes	Domestic and Foreign Earnings (Loss) Before Income Taxes DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Domestic earnings (loss) $ (268 ) $ 556 $ 643 Foreign earnings 55 251 73 Total earnings (loss) before income taxes $ (213 ) $ 807 $ 716
Provision (Benefit) for Income Taxes	Provision (Benefit) for Income Taxes DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Current: Federal $ 21 $ (69 ) $ 10 State 1 (5 ) — Foreign 10 61 82 Total current 32 (13 ) 92 Deferred: Federal (137 ) 45 61 State (31 ) 12 (18 ) Foreign (1 ) 15 (1 ) Total deferred (169 ) 72 42 Total income tax provision (benefit) $ (137 ) $ 59 $ 134
Effective Income Tax Rate Applicable	Effective Income Tax Rate DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 U.S. federal statutory income tax $ (45 ) $ 170 $ 250 State income taxes, net of federal tax benefit (31 ) 8 (2 ) REIT income not subject to federal income tax (68 ) (116 ) (198 ) SDT settlement (1) — 21 — Tax effect of U.S. corporate rate change (2) — — 74 Voluntary pension contribution (3) — (41 ) — Return to provision adjustment 4 (1 ) 2 Foreign taxes (2 ) 15 54 Repatriation of Canadian earnings — — (22 ) Other, net 5 3 (24 ) Total income tax provision (benefit) $ (137 ) $ 59 $ 134 Effective income tax rate 64.1% 7.3% 18.8% (1) In fourth quarter 2018, we recorded tax expense of $21 million related to the settlement of a dispute with the IRS. Refer to “Resolution of IRS Matter” below for further information. (2) In December 2017, H.R. 1 (the Tax Act) was enacted. The Tax Act contained significant changes to corporate taxation, including a reduction in the corporate tax rate from 35 percent to 21 percent. As a result of this change, we revalued our deferred tax assets and liabilities and recorded tax expense of $74 million during 2017, which reduced our net deferred tax asset. (3) At the end of 2017, we revalued our deferred tax assets and liabilities to the 21 percent federal tax rate prescribed by the Tax Act. During 2018, we made a voluntary contribution of $300 million to our U.S. qualified pension plan. We deducted this contribution on our 2017 U.S. federal tax return at the 2017 federal tax rate of 35 percent. This resulted in an incremental $41 million tax benefit for the portion attributable to our TRSs. Refer to Note 9: Pension and Other Postretirement Benefit Plans for further information on the voluntary contribution.
Balance Sheet Classification of Deferred Income Tax Assets (Liabilities)	Balance Sheet Classification of Deferred Income Tax Assets (Liabilities) DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Net noncurrent deferred tax asset $ 72 $ 15 Net noncurrent deferred tax liability (6 ) (43 ) Net deferred tax asset (liability) $ 66 $ (28 )
Items Included in Our Deferred Income Tax Assets (Liabilities)	Items Included in Our Deferred Income Tax Assets (Liabilities) DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 Deferred tax assets: Pension and postretirement benefits $ 159 $ 112 State tax credits 53 51 Depletion 34 41 Excess interest 55 30 Incentive compensation 17 20 Workers compensation 18 18 Net operating loss carryforwards 28 19 Other 101 96 Gross deferred tax assets 465 387 Valuation allowance (64 ) (61 ) Net deferred tax assets 401 326 Deferred tax liabilities: Property, plant and equipment (224 ) (197 ) Timber installment notes (74 ) (116 ) Other (37 ) (41 ) Net deferred tax liabilities (335 ) (354 ) Net deferred tax asset (liability) $ 66 $ (28 )

GEOGRAPHIC AREAS (Tables)

GEOGRAPHIC AREAS (Tables)	12 Months Ended
	Dec. 31, 2019
Segments Geographical Areas [Abstract]
Sales by Geographic Area	Sales by Geographic Area DOLLAR AMOUNTS IN MILLIONS 2019 2018 2017 Sales to unaffiliated customers: U.S. $ 5,674 $ 6,365 $ 6,168 Canada 440 519 472 Japan 305 410 352 China 90 120 107 Other foreign countries 45 62 97 Total $ 6,554 $ 7,476 $ 7,196 Export sales from the U.S.: Japan $ 265 $ 338 $ 295 China 85 113 102 Other foreign countries 129 153 148 Total $ 479 $ 604 $ 545
Long-Lived Assets by Geographic Area	Long-Lived Assets by Geographic Area DOLLAR AMOUNTS IN MILLIONS DECEMBER 31, 2019 DECEMBER 31, 2018 U.S. $ 14,074 $ 14,778 Canada 275 220 Total $ 14,349 $ 14,998

SELECTED QUARTERLY FINANCIAL _2

SELECTED QUARTERLY FINANCIAL INFORMATION (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Key Quarterly Financial Data	Key Quarterly Financial Data DOLLAR AMOUNTS IN MILLIONS, EXCEPT PER-SHARE FIGURES FIRST QUARTER SECOND QUARTER THIRD QUARTER FOURTH QUARTER FULL YEAR 2019: Net sales $ 1,643 $ 1,692 $ 1,671 $ 1,548 $ 6,554 Operating income $ 174 $ 186 $ 202 $ 89 $ 651 Earnings (loss) before income taxes $ (393 ) $ 91 $ 102 $ (13 ) $ (213 ) Net earnings (loss) $ (289 ) $ 128 $ 99 $ (14 ) $ (76 ) Basic and diluted net earnings (loss) per share $ (0.39 ) $ 0.17 $ 0.13 $ (0.02 ) $ (0.10 ) Dividends paid per share $ 0.34 $ 0.34 $ 0.34 $ 0.34 $ 1.36 2018: Net sales $ 1,865 $ 2,065 $ 1,910 $ 1,636 $ 7,476 Operating income $ 404 $ 476 $ 337 $ 177 $ 1,394 Earnings (loss) before income taxes $ 299 $ 382 $ 240 $ (114 ) $ 807 Net earnings (loss) $ 269 $ 317 $ 255 $ (93 ) $ 748 Basic and diluted net earnings (loss) per share $ 0.35 $ 0.42 $ 0.34 $ (0.12 ) $ 0.99 Dividends paid per share $ 0.32 $ 0.32 $ 0.34 $ 0.34 $ 1.32

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Negative book cash balances	$ 0	$ 0
Employee benefits retirement period	10 years
Net Sales | Customer Concentration Risk
Concentration risk, percentage	10.00%	10.00%
Canada | Minimum
Term of timber lease	15 years
Canada | Maximum
Term of timber lease	25 years

BUSINESS SEGMENTS - Sales and N

BUSINESS SEGMENTS - Sales and Net Contribution (Charge) to Earnings (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers	$ 1,548	$ 1,671	$ 1,692	$ 1,643	$ 1,636	$ 1,910	$ 2,065	$ 1,865	$ 6,554	$ 7,476	$ 7,196
Net contribution (charge) to earnings									165	1,182	1,109
Timberlands
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									1,618	1,873	1,893
RE & ENR
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									313	306	280
Wood Products
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									4,623	5,297	5,023
Operating segments | Timberlands
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									1,618	1,873	1,893
Net contribution (charge) to earnings									347	583	532
Operating segments | RE & ENR
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									313	306	280
Net contribution (charge) to earnings									144	127	146
Operating segments | Wood Products
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									4,623	5,297	5,023
Net contribution (charge) to earnings									353	838	569
Unallocated Items
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									0	0	0
Net contribution (charge) to earnings									(679)	(366)	(138)
Intersegment eliminations
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									(504)	(538)	(523)
Intersegment eliminations | Timberlands
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									503	537	522
Intersegment eliminations | RE & ENR
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									1	1	1
Intersegment eliminations | Wood Products
Segment Reporting, Revenue Reconciling Item
Sales to unaffiliated customers									$ 0	$ 0	$ 0

BUSINESS SEGMENTS - Reconciliat

BUSINESS SEGMENTS - Reconciliation of Net Contribution to Earnings to Net Earnings (Loss) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation From Segment Totals To Consolidated [Abstract]
Net contribution to earnings									$ 165	$ 1,182	$ 1,109
Interest expense, net of capitalized interest									(378)	(375)	(393)
Income (loss) before income taxes									(213)	807	716
Income taxes (Note 21)									137	(59)	(134)
Net earnings (loss)	$ (14)	$ 99	$ 128	$ (289)	$ (93)	$ 255	$ 317	$ 269	$ (76)	$ 748	$ 582

BUSINESS SEGMENTS - Additional

BUSINESS SEGMENTS - Additional Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	$ 510	$ 486	$ 521
Capital expenditures	384	427	419
Operating segments | Timberlands
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	301	319	356
Capital expenditures	112	117	115
Operating segments | RE & ENR
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	14	14	15
Capital expenditures	0	0	2
Operating segments | Wood Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	191	149	145
Capital expenditures	257	306	299
Unallocated Items
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation, depletion and amortization	4	4	5
Capital expenditures	$ 15	$ 4	$ 3

BUSINESS SEGMENTS - Total Asset

BUSINESS SEGMENTS - Total Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 16,406	$ 17,249
Operating segments | Timberlands and Real Estate & ENR
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	13,130	13,792
Operating segments | Wood Products
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	2,452	2,280
Unallocated Items
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 824	$ 1,177

REVENUE RECOGNITION Revenue by

REVENUE RECOGNITION Revenue by Major Products (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer
Net sales	$ 1,548	$ 1,671	$ 1,692	$ 1,643	$ 1,636	$ 1,910	$ 2,065	$ 1,865	$ 6,554	$ 7,476	$ 7,196
Timberlands
Revenue from External Customer
Net sales									1,618	1,873	1,893
Timberlands | Delivered logs
Revenue from External Customer
Net sales									1,472	1,711	1,649
Timberlands | Stumpage and pay-as-cut timber
Revenue from External Customer
Net sales									42	59	73
Timberlands | Recreational and other lease revenue
Revenue from External Customer
Net sales									61	59	59
Timberlands | Other
Revenue from External Customer
Net sales									43	44	112
Timberlands | West | Delivered logs
Revenue from External Customer
Net sales									740	987	915
Timberlands | South | Delivered logs
Revenue from External Customer
Net sales									640	625	616
Timberlands | North | Delivered logs
Revenue from External Customer
Net sales									92	99	95
Timberlands | Other | Delivered logs
Revenue from External Customer
Net sales									0	0	23
Timberlands | Domestic grade sales | West | Delivered logs
Revenue from External Customer
Net sales									375	503	473
Timberlands | Export grade sales | West | Delivered logs
Revenue from External Customer
Net sales									365	484	442
RE & ENR
Revenue from External Customer
Net sales									313	306	280
RE & ENR | Real Estate
Revenue from External Customer
Net sales									225	229	208
RE & ENR | Energy and natural resources
Revenue from External Customer
Net sales									88	77	72
Wood Products
Revenue from External Customer
Net sales									4,623	5,297	5,023
Wood Products | Structural lumber
Revenue from External Customer
Net sales									1,892	2,258	2,058
Wood Products | Oriented strand board
Revenue from External Customer
Net sales									632	891	904
Wood Products | Engineered solid section
Revenue from External Customer
Net sales									510	521	500
Wood Products | Engineered I-joists
Revenue from External Customer
Net sales									323	336	336
Wood Products | Softwood plywood
Revenue from External Customer
Net sales									161	200	176
Wood Products | Medium density fiberboard
Revenue from External Customer
Net sales									166	177	183
Wood Products | Complementary building products
Revenue from External Customer
Net sales									602	584	541
Wood Products | Other
Revenue from External Customer
Net sales									$ 337	$ 330	$ 325

DIVESTITURES AND ASSETS HELD _2

DIVESTITURES AND ASSETS HELD FOR SALE Additional Information (Details) $ in Millions	Dec. 17, 2019USD ($)a	Nov. 13, 2019USD ($)	Sep. 16, 2019a	Sep. 01, 2017USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from disposition of operations (Note 4)						$ 0	$ 0	$ 403
Impairment charges					$ 80	80
Assets held for sale					$ 140	140	$ 0
Uruguay Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from disposition of operations (Note 4)				$ 403
Michigan | Lyme Timber Company LP
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of acers of timberlands agreed to be sold | a			555,000
Proceeds from disposition of operations (Note 4)		$ 297
Gain on sale of discontinued and other operations		$ 48
Montana
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of acers of timberlands agreed to be sold | a	630,000
Cash to be received from sale of timberlands	$ 145
Impairment charges						$ 80

NET EARNINGS (LOSS) PER SHARE -

NET EARNINGS (LOSS) PER SHARE - Additional Information (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings (loss) per share, basic and diluted	$ (0.10)	$ 0.99	$ 0.77

NET EARNINGS (LOSS) PER SHARE_2

NET EARNINGS (LOSS) PER SHARE - Schedule of Earning (Loss) per share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share Basic And Diluted [Line Items]
Basic	745,897	754,556	753,085
Dilutive potential common shares	0	2,271	3,581
Diluted	745,897	756,827	756,666
Stock options
Earnings Per Share Basic And Diluted [Line Items]
Dilutive potential common shares	0	1,310	2,571
Restricted stock units
Earnings Per Share Basic And Diluted [Line Items]
Dilutive potential common shares	0	566	582
Performance share units
Earnings Per Share Basic And Diluted [Line Items]
Dilutive potential common shares	0	395	428

NET EARNINGS (LOSS) PER SHARE_3

NET EARNINGS (LOSS) PER SHARE - Schedule of Potential Shares Not Included in the Computation of Diluted Earnings (Loss) Per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares not included in the computation of diluted earnings (loss) per share	2,631	2,402	1,351
Restricted stock units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares not included in the computation of diluted earnings (loss) per share	477	0	0
Performance share units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares not included in the computation of diluted earnings (loss) per share	1,131	1,080	799

INVENTORIES Inventories (Detail

INVENTORIES Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Inventory [Line Items]
Total	$ 416	$ 389
Logs
Inventory [Line Items]
LIFO inventories	19	11
FIFO or moving average cost inventories	28	35
Lumber, plywood, panels and fiberboard
Inventory [Line Items]
LIFO inventories	82	75
Lumber, plywood, panels, fiberboard and engineered wood products
Inventory [Line Items]
FIFO or moving average cost inventories	84	86
Other products
Inventory [Line Items]
LIFO inventories	10	10
FIFO or moving average cost inventories	98	83
Materials and supplies
Inventory [Line Items]
FIFO or moving average cost inventories	$ 95	$ 89

INVENTORIES Additional informat

INVENTORIES Additional information (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Increase in inventory amount if FIFO would have been used	$ 76	$ 79

PROPERTY AND EQUIPMENT - Carryi

PROPERTY AND EQUIPMENT - Carrying Value of Property and Equipment and Estimated Service Lives (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Property and Equipment [Line Items]
Property and equipment, at cost	$ 5,446	$ 5,233
Accumulated depreciation and amortization	(3,477)	(3,376)
Property and equipment, net	1,969	1,857
Land
Property and Equipment [Line Items]
Property and equipment, at cost	87	87
Buildings and improvements
Property and Equipment [Line Items]
Property and equipment, at cost	$ 999	942
Buildings and improvements | Minimum
Property and Equipment [Line Items]
Estimated service lives	15 years
Buildings and improvements | Maximum
Property and Equipment [Line Items]
Estimated service lives	40 years
Machinery and Equipment
Property and Equipment [Line Items]
Property and equipment, at cost	$ 3,425	3,240
Machinery and Equipment | Minimum
Property and Equipment [Line Items]
Estimated service lives	5 years
Machinery and Equipment | Maximum
Property and Equipment [Line Items]
Estimated service lives	25 years
Roads
Property and Equipment [Line Items]
Property and equipment, at cost	$ 742	785
Roads | Minimum
Property and Equipment [Line Items]
Estimated service lives	10 years
Roads | Maximum
Property and Equipment [Line Items]
Estimated service lives	35 years
Other
Property and Equipment [Line Items]
Property and equipment, at cost	$ 193	$ 179
Other | Minimum
Property and Equipment [Line Items]
Estimated service lives	3 years
Other | Maximum
Property and Equipment [Line Items]
Estimated service lives	10 years

PROPERTY AND EQUIPMENT - Additi

PROPERTY AND EQUIPMENT - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property and Equipment [Line Items]
Depreciation and amortization expense	$ 510	$ 486	$ 521
Property and Equipment
Property and Equipment [Line Items]
Depreciation and amortization expense	$ 240	$ 197	$ 206

RELATED PARTIES - Additional In

RELATED PARTIES - Additional Information (Details) $ in Millions	1 Months Ended	3 Months Ended			12 Months Ended
	Oct. 31, 2017USD ($)	Sep. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)a
Related Party Transaction [Line Items]
Current restricted financial investments held by variable interest entities (Note 8)				$ 253	$ 362	$ 253
Proceeds from note receivable held by variable interest entities			$ 253
Payments related to SPE liabilities		$ 302		$ 209
Interest expense					378	375	$ 393
Proceeds from sale of Southern timberlands					297	0	203
Gain on sale of timberlands					48	0	99
Buyer-sponsored SPEs
Related Party Transaction [Line Items]
Interest income					22	34	34
Interest expense					$ 12	$ 29	$ 29
Weighted average interest rate on SPE financial investments					5.50%	5.50%
Monetization SPEs
Related Party Transaction [Line Items]
Weighted average interest rate on SPE long-term notes					5.60%	5.60%
Twin Creeks Venture
Related Party Transaction [Line Items]
Ownership interest	21.00%
Proceeds from redemption of ownership interest in related party	$ 108
Sale of Timberland acreage | a							100,000
Proceeds from sale of Southern timberlands							$ 203
Gain on sale of timberlands							$ 99
Twin Creeks Venture | Mississippi
Related Party Transaction [Line Items]
Sale of Timberland acreage | a							80,000
Twin Creeks Venture | Georgia
Related Party Transaction [Line Items]
Sale of Timberland acreage | a							20,000

PENSION AND OTHER POSTRETIREM_3

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended					11 Months Ended	12 Months Ended
	Oct. 31, 2019	Jan. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net effect of remeasurement reduction in funded status										$ 24
Defined Benefit Plan, Plan Assets, Period Increase (Decrease)							$ 16
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)							6
Defined Benefit Plan Funded Status Period Increase Decrease							$ 22
Pension plans with projected benefit obligations greater than plan assets, projected benefit obligations					$ 4,500			$ 3,400		3,400	$ 4,500
Pension plans with projected benefit obligations greater than plan assets, fair value of assets					4,100			2,800		2,800	4,100
Pension plans with accumulated benefit obligations greater than plan assets, accumulated benefit obligations					4,400			3,300		3,300	4,400
Pension plans with accumulated benefit obligations greater than plan assets, fair value of assets					4,100			2,800		2,800	4,100
Accumulated benefit obligation for all defined benefit pension plans					$ 5,200			$ 4,200		4,200	5,200
Employer contributions and benefit payments										25	$ 22	$ 21
U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan										$ (1,500)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.40%								4.30%
Canada
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year					4.90%			5.40%		5.40%	4.90%
Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					$ 330			$ 99		$ 99	$ 330	557
Expected return on plan assets										2.70%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Period Increase (Decrease), Percentage							1.00%
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease), Percentage							1.00%
U.S. Qualified Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan										$ (1,500)
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.40%						4.30%
Payment for Pension Benefits						$ 300					300
Qualified and Registered Plans
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets										7.00%
Qualified and Registered Plans | Scenario Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets									6.50%
Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					$ 4,920			$ 3,709		$ 3,709	$ 4,920
Pre Medicare | U.S.
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year					7.80%			7.30%		7.30%	7.80%
Health Reimbursement Account | U.S.
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year					4.50%			4.50%		4.50%	4.50%
Registered Pension Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Employer contributions and benefit payments										$ 10
Registered Pension Plans | Canada | Scenario Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to benefit plans during 2020									$ 2
Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					$ 10			$ 10		10	$ 10
Employer contributions and benefit payments										2
Non Registered Plans | Canada | Scenario Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to benefit plans during 2020									3
Non Registered Plans | Fair Value, Inputs, Level 3 | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0			0		0	0
Non Qualified Pension Plans Defined Benefit | U.S.
Defined Benefit Plan Disclosure [Line Items]
Employer contributions and benefit payments										18
Non Qualified Pension Plans Defined Benefit | U.S. | Scenario Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to benefit plans during 2020									$ 17
Pension
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan										1	1
Defined Benefit Plan, Plan Assets, Payment for Settlement	$ 6		$ 449	$ 455	200
Reduction in settlement charge			$ 6							(455)	(200)	0
Defined Benefit Plan, Plan Assets, Benefits Paid					664					1,745	1,024
Fair value of plan assets					$ 4,930			$ 3,719		3,719	4,930	$ 5,514
Employer contributions and benefit payments										$ 30	$ 345
Pension | U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate										4.30%	3.70%	4.30%
Discount rates, benefit obligation					4.40%			3.40%		3.40%	4.40%
Pension | Canada
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate										3.70%	3.50%	3.70%
Discount rates, benefit obligation					3.70%			3.10%		3.10%	3.70%
Pension | Qualified and Registered Plans
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets										7.00%	8.00%	8.00%
U.S. Qualified Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Payment for Pension Benefits											$ 300
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan										$ 0	0
Reduction in settlement charge										0	0	$ 0
Defined Benefit Plan, Plan Assets, Benefits Paid										17	22
Fair value of plan assets					$ 18			$ 19		19	18	$ 0
Employer contributions and benefit payments										15	$ 36
Expected contribution to benefit plans during 2020								9		9
Other Postretirement Benefits | Collective Bargaining Arrangement
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to benefit plans during 2020								$ 5		$ 5
Other Postretirement Benefits | U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate										4.20%	3.50%	3.70%
Discount rates, benefit obligation					4.20%			3.00%		3.00%	4.20%
Employer contributions and benefit payments										$ 11
Other Postretirement Benefits | Canada
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate										3.70%	3.40%	3.60%
Discount rates, benefit obligation					3.70%			3.00%		3.00%	3.70%
Weighted health care cost trend rate assumed for next year								4.90%		4.90%
Employer contributions and benefit payments										$ 4
Other Postretirement Benefits | Pre Medicare | U.S.
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year								7.80%		7.80%
Other Postretirement Benefits | Health Reimbursement Account | U.S.
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year								4.50%		4.50%

PENSION AND OTHER POSTRETIREM_4

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Funded Status of Our Plans (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3,719	$ 4,930	$ 5,514
Projected benefit obligations	(4,260)	(5,263)	(6,795)
Funded status	(541)	(333)
Noncurrent assets	47	74
Current liabilities	(19)	(18)
Noncurrent liabilities	(569)	(389)
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	19	18	0
Projected benefit obligations	(151)	(166)	$ (200)
Funded status	(132)	(148)
Noncurrent assets	0	0
Current liabilities	(8)	(10)
Noncurrent liabilities	$ (124)	$ (138)

PENSION AND OTHER POSTRETIREM_5

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Changes in Fair Value of Plan Assets (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)		$ 4,930	$ 5,514
Adjustment for final fair value of plan assets		16	44
Actual return on plan assets		449	123
Foreign currency translation		38	(73)
Employer contributions and benefit payments		30	345
Plan participants’ contributions		0	0
Plan transfers		1	1
Benefits paid (includes lump sum and annuity transfers)	$ (664)	(1,745)	(1,024)
Fair value of plan assets at end of year (estimated)	4,930	3,719	4,930
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)		18	0
Adjustment for final fair value of plan assets		0	0
Actual return on plan assets		1	0
Foreign currency translation		0	0
Employer contributions and benefit payments		15	36
Plan participants’ contributions		2	4
Plan transfers		0	0
Benefits paid (includes lump sum and annuity transfers)		(17)	(22)
Fair value of plan assets at end of year (estimated)	$ 18	$ 19	$ 18

PENSION AND OTHER POSTRETIREM_6

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Changes in Projected Benefit Obligations of Our Pension and Other Postretirement Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation beginning of year	$ 5,263	$ 6,795
Service cost	32	37	$ 35
Interest cost	160	236	264
Plan participants’ contributions	0	0
Actuarial (gains) losses	510	(718)
Foreign currency translation	39	(69)
Benefits paid (includes lump sum and annuity transfers)	(1,745)	(1,024)
Plan amendments and other	0	5
Plan transfers	1	1
Projected benefit obligation at end of year	4,260	5,263	6,795
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation beginning of year	166	200
Service cost	0	0	0
Interest cost	6	7	8
Plan participants’ contributions	2	4
Actuarial (gains) losses	(8)	(18)
Foreign currency translation	2	(5)
Benefits paid (includes lump sum and annuity transfers)	(17)	(22)
Plan amendments and other	0	0
Plan transfers	0	0
Projected benefit obligation at end of year	$ 151	$ 166	$ 200

PENSION AND OTHER POSTRETIREM_7

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Assets Within Our U.S. and Canadian Qualified and Registered Pension Plans (Details) - Qualified and Registered Plans	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	100.00%	100.00%
Cash and short-term investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	3.20%	5.80%
Fixed income investments, Corporate
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	33.90%	21.50%
Government
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	25.40%	8.60%
Fixed Income Investments, Repurchase Agreements
Defined Benefit Plan Disclosure [Line Items]
Repurchase agreements	(4.70%)	0.00%
Hedge funds and related investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	14.30%	36.90%
Public equity investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	0.10%	0.00%
Private equity and related investments
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	27.70%	21.90%
Derivative instruments, net
Defined Benefit Plan Disclosure [Line Items]
Assets invested in pension plan, allocation percentage	0.30%	5.60%
Accrued liabilities
Defined Benefit Plan Disclosure [Line Items]
Repurchase agreements	(0.20%)	(0.30%)

PENSION AND OTHER POSTRETIREM_8

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Net Pension Plan Assets, by Fair Value Hierarchy (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3,719	$ 4,930	$ 5,514
Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,709	4,920
Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	10
Non Registered Plans | Net Asset Value | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and short-term investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	120	287
Cash and short-term investments | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and short-term investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	5
Cash and short-term investments | Non Registered Plans | Net Asset Value | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fixed Income Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,260	1,054
Fixed Income Investments | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fixed Income Investments, Government | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	941	426
Fixed Income Investments, Government | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fixed Income Investments, Repurchase Agreements | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(176)
Fixed Income Investments, Repurchase Agreements | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Public Equity Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4
Public Equity Investments | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Hedge funds and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	531	1,814
Hedge funds and related investments | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	518	1,811
Private equity and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,028	1,079
Private equity and related investments | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	942	1,014
Derivative instruments, net | Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	277
Derivative instruments, net | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	277
Derivative instruments, net | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,718	4,937
Investments | Qualified and Registered Plans | Net Asset Value | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,460	2,825
Accrued liabilities | Qualified and Registered Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(9)	(17)
Public equity investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	5
Public equity investments | Non Registered Plans | Net Asset Value | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1 | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	10
Fair Value, Inputs, Level 1 | Cash and short-term investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	120	275
Fair Value, Inputs, Level 1 | Cash and short-term investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	5
Fair Value, Inputs, Level 1 | Fixed Income Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1 | Fixed Income Investments, Government | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1 | Fixed Income Investments, Repurchase Agreements | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fair Value, Inputs, Level 1 | Public Equity Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4
Fair Value, Inputs, Level 1 | Hedge funds and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1 | Private equity and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1 | Derivative instruments, net | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1 | Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	124	275
Fair Value, Inputs, Level 1 | Public equity investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	5
Fair Value, Inputs, Level 2 | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 2 | Cash and short-term investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	12
Fair Value, Inputs, Level 2 | Cash and short-term investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 2 | Fixed Income Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,260	1,054
Fair Value, Inputs, Level 2 | Fixed Income Investments, Government | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	941	426
Fair Value, Inputs, Level 2 | Fixed Income Investments, Repurchase Agreements | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(176)
Fair Value, Inputs, Level 2 | Public Equity Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fair Value, Inputs, Level 2 | Hedge funds and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 2 | Private equity and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 2 | Derivative instruments, net | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	15
Fair Value, Inputs, Level 2 | Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,035	1,507
Fair Value, Inputs, Level 2 | Public equity investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	99	330	557
Fair Value, Inputs, Level 3 | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 3 | Cash and short-term investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 3 | Cash and short-term investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 3 | Fixed Income Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 3 | Fixed Income Investments, Government | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 3 | Fixed Income Investments, Repurchase Agreements | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fair Value, Inputs, Level 3 | Public Equity Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fair Value, Inputs, Level 3 | Hedge funds and related investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13	3	10
Fair Value, Inputs, Level 3 | Hedge funds and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13	3
Fair Value, Inputs, Level 3 | Private equity and related investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	86	65	102
Fair Value, Inputs, Level 3 | Private equity and related investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	86	65
Fair Value, Inputs, Level 3 | Derivative instruments, net
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	262	$ 445
Fair Value, Inputs, Level 3 | Derivative instruments, net | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	262
Fair Value, Inputs, Level 3 | Investments | Qualified and Registered Plans | U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	99	330
Fair Value, Inputs, Level 3 | Public equity investments | Non Registered Plans | Canada
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

PENSION AND OTHER POSTRETIREM_9

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Reconciliation of Pension Plan Assets Measured at Level 3 Fair Value (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	$ 330	$ 557
Net realized gains (losses)	237	238
Net change in unrealized gains (losses)	(263)	(188)
Purchases	0	5
Sales	(6)	(2)
Settlements	(237)	(237)
Transfers into Level 3	41	18
Transfers out of Level 3	(3)	(61)
Fair value of plan assets at end of year (estimated)	99	330
Hedge funds and related investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	3	10
Net realized gains (losses)	1	0
Net change in unrealized gains (losses)	(1)	1
Purchases	0	0
Sales	(3)	0
Settlements	0	0
Transfers into Level 3	13	0
Transfers out of Level 3	0	(8)
Fair value of plan assets at end of year (estimated)	13	3
Private equity and related investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	65	102
Net realized gains (losses)	(1)	0
Net change in unrealized gains (losses)	0	(5)
Purchases	0	5
Sales	(3)	(2)
Settlements	0	0
Transfers into Level 3	28	18
Transfers out of Level 3	(3)	(53)
Fair value of plan assets at end of year (estimated)	86	65
Derivative instruments, net
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	262	445
Net realized gains (losses)	237	238
Net change in unrealized gains (losses)	(262)	(184)
Purchases	0	0
Sales	0	0
Settlements	(237)	(237)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value of plan assets at end of year (estimated)	$ 0	$ 262

PENSION AND OTHER POSTRETIRE_10

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Fair Value and Aggregate Notional Amount of the Derivative Instruments Held by our Pension Trusts (Details) - Pension - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3,719	$ 4,930	$ 5,514
Foreign currency derivatives, net
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Derivative, notional amount	0	13
Future
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	15
Derivative, notional amount	813	1,073
Total return swaps, net
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	262
Derivative, notional amount	0	558
Derivative instruments, net
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	277
Derivative, notional amount	$ 813	$ 1,644

PENSION AND OTHER POSTRETIRE_11

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Rates We Use in Estimating Our Benefit Obligations (Details) - Pension	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Lump sum or installment distributions election	60.00%	60.00%
U.S.
Defined Benefit Plan Disclosure [Line Items]
Discount rates, benefit obligation	3.40%	4.40%
Canada
Defined Benefit Plan Disclosure [Line Items]
Discount rates, benefit obligation	3.10%	3.70%
Salaried | Canada
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.25%	3.25%
Hourly | Canada
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	3.00%	3.00%
Maximum | Salaried | U.S.
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	13.00%	13.00%
Maximum | Hourly | U.S.
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	13.00%	13.00%
Minimum | Salaried | U.S.
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	2.00%	2.00%
Minimum | Hourly | U.S.
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	2.30%	2.30%

PENSION AND OTHER POSTRETIRE_12

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Rates Used to Estimate Our Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Qualified and Registered Plans
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets		7.00%
U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.40%	4.30%
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan		$ (1,500)
Pension
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan		$ 1	$ 1
Pension | Qualified and Registered Plans
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets		7.00%	8.00%	8.00%
Pension | U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.30%	3.70%	4.30%
Lump sum distributions election		60.00%	60.00%	60.00%
Pension | U.S. | Salaried | Maximum
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase		13.00%	13.00%	13.00%
Pension | U.S. | Salaried | Minimum
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase		2.00%	2.00%	2.00%
Pension | U.S. | Hourly | Maximum
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase		13.00%	13.00%	13.00%
Pension | U.S. | Hourly | Minimum
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase		2.30%	2.30%	2.30%
Pension | Canada
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		3.70%	3.50%	3.70%
Pension | Canada | Salaried
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase		3.25%	3.25%	3.50%
Pension | Canada | Hourly
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase		3.00%	3.00%	3.25%

PENSION AND OTHER POSTRETIRE_13

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Assumptions We Use in Estimating Health Care Benefit Costs (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
U.S.
Defined Benefit Plan Disclosure [Line Items]
Rate that the cost trend rate gradually declines to	4.50%	4.50%
Year the cost trend rate is reached	2037	2037
Canada
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year	5.40%	4.90%
Rate that the cost trend rate gradually declines to	4.00%	4.00%
Year the cost trend rate is reached	2039	2039
Pre Medicare | U.S.
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year	7.30%	7.80%
Health Reimbursement Account | U.S.
Defined Benefit Plan Disclosure [Line Items]
Weighted health care cost trend rate assumed for next year	4.50%	4.50%

PENSION AND OTHER POSTRETIRE_14

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Net Periodic Benefit Cost (Credit) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 32	$ 37	$ 35
Interest cost		160	236	264
Expected return on plan assets		(223)	(399)	(409)
Amortization of actuarial loss		112	225	195
Amortization of prior service cost (credit)		4	3	4
Settlement charges	$ (6)	455	200	0
Net periodic benefit cost (credit)		540	302	89
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost		0	0	0
Interest cost		6	7	8
Expected return on plan assets		0	0	0
Amortization of actuarial loss		7	8	8
Amortization of prior service cost (credit)		(5)	(8)	(8)
Settlement charges		0	0	0
Net periodic benefit cost (credit)		$ 8	$ 7	$ 8

PENSION AND OTHER POSTRETIRE_15

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Estimated Projected Benefit Payments for the Next 10 Years (Details) $ in Millions	Dec. 31, 2019USD ($)
Pension
Defined Benefit Plan Disclosure [Line Items]
Expected Future Benefit Payments 2020	$ 237
Expected Future Benefit Payments 2021	235
Expected Future Benefit Payments 2022	236
Expected Future Benefit Payments 2023	238
Expected Future Benefit Payments 2024	237
Expected Future Benefit Payments 2025-2029	1,176
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Expected Future Benefit Payments 2020	14
Expected Future Benefit Payments 2021	13
Expected Future Benefit Payments 2022	13
Expected Future Benefit Payments 2023	12
Expected Future Benefit Payments 2024	11
Expected Future Benefit Payments 2025-2029	$ 47

ACCRUED LIABILITIES Accrued Lia

ACCRUED LIABILITIES Accrued Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities Current [Abstract]
Compensation and employee benefit costs	$ 188	$ 192
Current portion of lease liabilities (Note 17)	33	0
Customer rebates, volume discounts and deferred income	105	99
Interest	98	109
Taxes payable	24	30
Other	82	60
Total	$ 530	$ 490

LINES OF CREDIT - Additional In

LINES OF CREDIT - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Line Of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity				$ 1,500,000,000
Line of credit expiration date		Mar. 31, 2022
Line of credit, amount outstanding		$ 230,000,000	$ 425,000,000
Line of credit, remaining borrowing capacity		1,270,000,000
Compensating balance requirements for our letters of credit		$ 3,000,000	$ 6,000,000
Subsequent Event | Amended and Restated
Line Of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 1,500,000,000
Line of credit expiration date	Jan. 31, 2025

LINES OF CREDIT - Letters of Cr

LINES OF CREDIT - Letters of Credit and Surety Bonds (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Short Term Debt Other Disclosures [Abstract]
Letters of credit	$ 35	$ 38
Surety bonds	$ 127	$ 123

LONG-TERM DEBT - Additional Inf

LONG-TERM DEBT - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended	12 Months Ended
	Mar. 31, 2019	Feb. 28, 2018	Mar. 31, 2019	Dec. 31, 2019	Feb. 28, 2019
Debt Instrument [Line Items]
Proceeds from debt, net of issuance costs				$ 739
Pretax charge related to early extinguishment of debt			$ 12
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 500		$ 500
Unamortized discounts, capitalized debt expense and fair value adjustments				$ 3
4.00 percent due in November 2029
Debt Instrument [Line Items]
Debt issued					$ 750
Debt instrument, interest rate, stated percentage					4.00%
Debt, maturity date				Nov. 30, 2029
7.38 percent due in October 2019
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	7.38%		7.38%
Debt, maturity date				Oct. 31, 2019
Repayments of debt	$ 500
7.00 percent debentures due 2018
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		7.00%
Repayments of debt		$ 62

LONG-TERM DEBT - Long-Term Debt

LONG-TERM DEBT - Long-Term Debt by Types and Interest Rates (Includes Current Portion) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Other	$ 1	$ 1
Total principal long-term debt	6,144	5,894
Less: unamortized discounts	(14)	(5)
Less: unamortized debt expense	(10)	(9)
Total	6,147	5,919
Portion due within one year	0	500
Plum Creek
Debt Instrument [Line Items]
Add: fair value adjustments (related to Plum Creek merger)	27	39
7.375% debentures due 2019
Debt Instrument [Line Items]
Senior Notes	$ 0	$ 500
Debt, interest rate	7.375%	7.375%
Debt, maturity date	Dec. 31, 2019	Dec. 31, 2019
9.00% debentures due 2021
Debt Instrument [Line Items]
Senior Notes	$ 150	$ 150
Debt, interest rate	9.00%	9.00%
Debt, maturity date	Dec. 31, 2021	Dec. 31, 2021
4.70% debentures due 2021
Debt Instrument [Line Items]
Senior Notes	$ 569	$ 569
Debt, interest rate	4.70%	4.70%
Debt, maturity date	Dec. 31, 2021	Dec. 31, 2021
7.125% debentures due 2023
Debt Instrument [Line Items]
Senior Notes	$ 191	$ 191
Debt, interest rate	7.125%	7.125%
Debt, maturity date	Dec. 31, 2023	Dec. 31, 2023
5.207% debentures due 2023
Debt Instrument [Line Items]
Senior Notes	$ 860	$ 860
Debt, interest rate	5.207%	5.207%
Debt, maturity date	Dec. 31, 2023	Dec. 31, 2023
4.625% notes due 2023
Debt Instrument [Line Items]
Senior Notes	$ 500	$ 500
Debt, interest rate	4.625%	4.625%
Debt, maturity date	Dec. 31, 2023	Dec. 31, 2023
3.25% debentures due 2023
Debt Instrument [Line Items]
Senior Notes	$ 325	$ 325
Debt, interest rate	3.25%	3.25%
Debt, maturity date	Dec. 31, 2023	Dec. 31, 2023
8.50% debentures due 2025
Debt Instrument [Line Items]
Senior Notes	$ 300	$ 300
Debt, interest rate	8.50%	8.50%
Debt, maturity date	Dec. 31, 2025	Dec. 31, 2025
7.95% debentures due 2025
Debt Instrument [Line Items]
Senior Notes	$ 136	$ 136
Debt, interest rate	7.95%	7.95%
Debt, maturity date	Dec. 31, 2025	Dec. 31, 2025
7.70% debentures due 2026
Debt Instrument [Line Items]
Senior Notes	$ 150	$ 150
Debt, interest rate	7.70%	7.70%
Debt, maturity date	Dec. 31, 2026	Dec. 31, 2026
7.35% debentures due 2026
Debt Instrument [Line Items]
Senior Notes	$ 62	$ 62
Debt, interest rate	7.35%	7.35%
Debt, maturity date	Dec. 31, 2026	Dec. 31, 2026
7.85% debentures due 2026
Debt Instrument [Line Items]
Senior Notes	$ 100	$ 100
Debt, interest rate	7.85%	7.85%
Debt, maturity date	Dec. 31, 2026	Dec. 31, 2026
Variable rate term loan credit facility matures 2026
Debt Instrument [Line Items]
Term loan credit facility	$ 225	$ 225
Debt, maturity date	Dec. 31, 2026	Dec. 31, 2026
6.95% debentures due 2027
Debt Instrument [Line Items]
Senior Notes	$ 300	$ 300
Debt, interest rate	6.95%	6.95%
Debt, maturity date	Dec. 31, 2027	Dec. 31, 2027
4.00% debentures due 2029
Debt Instrument [Line Items]
Senior Notes	$ 750	$ 0
Debt, interest rate	4.00%	4.00%
Debt, maturity date	Dec. 31, 2029	Dec. 31, 2029
7.375% debentures due 2032
Debt Instrument [Line Items]
Senior Notes	$ 1,250	$ 1,250
Debt, interest rate	7.375%	7.375%
Debt, maturity date	Dec. 31, 2032	Dec. 31, 2032
6.875% debentures due 2033
Debt Instrument [Line Items]
Senior Notes	$ 275	$ 275
Debt, interest rate	6.875%	6.875%
Debt, maturity date	Dec. 31, 2033	Dec. 31, 2033

LONG-TERM DEBT - Amounts of Lon

LONG-TERM DEBT - Amounts of Long-Term Debt Due Annually for the Next Five Years and Thereafter (Details) $ in Millions	Dec. 31, 2019USD ($)
Debt Disclosure [Abstract]
2020	$ 0
2021	719
2022	0
2023	1,876
2024	0
Thereafter	$ 3,549

FAIR VALUE OF FINANCIAL INSTR_3

FAIR VALUE OF FINANCIAL INSTRUMENTS Estimated Fair Values and Carrying Values of Long-Term Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
FAIR VALUE OF FINANCIAL INSTRUMENTS
Long-term debt (including current maturities) and line of credit, carrying value	$ 6,377	$ 6,344
Long-term debt (including current maturities) and line of credit, fair value (Level 2)	7,441	6,995
Fixed interest rate
FAIR VALUE OF FINANCIAL INSTRUMENTS
Long-term debt (including current maturities) and line of credit, carrying value	5,922	5,694
Long-term debt (including current maturities) and line of credit, fair value (Level 2)	6,986	6,345
Variable interest rate
FAIR VALUE OF FINANCIAL INSTRUMENTS
Long-term debt (including current maturities) and line of credit, carrying value	455	650
Long-term debt (including current maturities) and line of credit, fair value (Level 2)	$ 455	$ 650

LEGAL PROCEEDINGS, COMMITMENT_3

LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES - Changes in the Reserve for Environmental Remediation (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Accrual For Environmental Loss Contingencies Disclosure [Abstract]
Reserve balance as of December 31, 2018	$ 62
Reserve charges and adjustments, net	4
Payments	(5)
Reserve balance as of December 31, 2019	$ 61

LEGAL PROCEEDINGS, COMMITMENT_4

LEGAL PROCEEDINGS, COMMITMENTS AND CONTINGENCIES - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Remediation costs for all identified sites may exceed reserves	$ 124
Asset retirement obligations	$ 30	$ 29

SHAREHOLDERS' INTEREST - Additi

SHAREHOLDERS' INTEREST - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Feb. 07, 2019
Class Of Stock [Line Items]
Shares repurchased during period	2,349,000	11,410,000	0
Unsettled share repurchases	$ 0	$ 0
2019 Repurchase Program
Class Of Stock [Line Items]
Stock repurchase program, authorized amount				$ 500,000,000
Shares repurchased during period	2,300,000
Shares repurchased during period value	$ 60,000,000
Stock repurchase program, remaining authorized repurchase amount	$ 440,000,000
2016 Repurchase Program
Class Of Stock [Line Items]
Shares repurchased during period		11,400,000	0
Shares repurchased during period value		$ 366,000,000
Stock repurchase program, remaining authorized repurchase amount		$ 135,000,000
Preferred shares
Class Of Stock [Line Items]
Preferred shares, outstanding	0	0
Preferred shares, authorized	7,000,000	40,000,000
Preferred shares, par value	$ 1	$ 1

SHAREHOLDERS' INTEREST - Reconc

SHAREHOLDERS' INTEREST - Reconciliation of Our Common Share Activity (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Class Of Stock [Line Items]
Outstanding at beginning of year	746,391	755,223	748,528
Repurchased	(2,349)	(11,410)	0
Outstanding at end of year	745,300	746,391	755,223
Stock options
Class Of Stock [Line Items]
Stock issued under share-based payment arrangement	660	2,026	5,970
Vested restricted stock units
Class Of Stock [Line Items]
Stock issued under share-based payment arrangement	480	466	605
Vested performance share units
Class Of Stock [Line Items]
Stock issued under share-based payment arrangement	118	86	120

SHAREHOLDERS' INTEREST - Change

SHAREHOLDERS' INTEREST - Changes in Amounts Included in Our Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of year	$ 9,046	$ 8,899
Translation adjustments	26	(54)	$ 32
Reclassification of certain effects due to tax law changes		(253)
Reclassification of accumulated unrealized gains on available-for-sale securities		(9)
Balance at end of year	8,177	9,046	8,899
Pension
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of year	(1,343)	(1,810)	(1,660)
Other comprehensive income (loss) before reclassifications	(216)	388	(282)
Amounts reclassified from accumulated other comprehensive income (loss) to earnings	431	325	132
Total other comprehensive income (loss)	215	713	(150)
Reclassification of certain effects due to tax law changes	0	(246)	0
Balance at end of year	(1,128)	(1,343)	(1,810)
Defined Benefit Plan, Plan Assets, Payment for Settlement	455	200
Other Postretirement Benefits
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of year	(19)	(25)	(38)
Other comprehensive income (loss) before reclassifications	6	13	14
Amounts reclassified from accumulated other comprehensive income (loss) to earnings	1	0	(1)
Total other comprehensive income (loss)	7	13	13
Reclassification of certain effects due to tax law changes	0	(7)	0
Balance at end of year	(12)	(19)	(25)
Translation Adjustment And Other
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of year	210	273	239
Translation adjustments	26	(54)	34
Total other comprehensive income (loss)	26	(54)	34
Reclassification of accumulated unrealized gains on available-for-sale securities	0	(9)	0
Balance at end of year	236	210	273
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of year	(1,152)	(1,562)	(1,459)
Balance at end of year	$ (904)	$ (1,152)	$ (1,562)

SHARE-BASED COMPENSATION - Addi

SHARE-BASED COMPENSATION - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense	$ 30,000,000	$ 42,000,000	$ 40,000,000
Number of shares available for future grants under the Plan	20,000,000
Increase in number of common shares if all share-based awards were exercised or vested	28,000,000
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 4,000,000	$ 5,000,000	$ 6,000,000
Unrecognized share-based compensation cost for non-vested equity-classified share-based compensation arrangements	$ 36,000,000
Unrecognized share-based compensation costs for non-vested equity-classified share-based compensation arrangements, weighted average period for recognition	1 year 2 months 12 days
Number of common shares to be issued for directors who elected common share payments subsequent to year-end	674,000
Number of stock-equivalent units outstanding in deferred compensation accounts	788,000	788,000	804,000
Restricted stock, restricted stock units, performance shares, performance share units, or other equity grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of shares an individual may receive in one year	1,000,000
Value of awards a participant may be granted in a 12 month period	$ 10,000,000
Stock options and stock appreciation rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of shares an individual may receive in one year	2,000,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Weighted average grant-date fair value	$ 25.83	$ 34.19	$ 32.83
Total grant-date fair value vested	$ 18,000,000	$ 16,000,000	$ 18,000,000
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average grant-date fair value	$ 29.66	$ 35.49	$ 37.93
Total grant-date fair value vested	$ 3,000,000	$ 4,000,000	$ 4,000,000
Performance share units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Final number of shares awarded of each grant's target	0.00%
Performance share units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Final number of shares awarded of each grant's target	150.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Total intrinsic value of stock options exercised	$ 5,000,000	$ 22,000,000	$ 68,000,000

SHARE-BASED COMPENSATION - Sche

SHARE-BASED COMPENSATION - Schedule of Restricted Stock Units Activity (Details) - Restricted stock units - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Units
Balance, beginning of year	1,593
Granted	865
Vested	(582)
Forfeited	(87)
Balance, end of year	1,789	1,593
Nonvested performance share units that have met the requisite service period and will be released as identified in the grant terms	526
Weighted Average Grant Date Fair Value
Balance, beginning of year	$ 31.41
Granted	25.83	$ 34.19	$ 32.83
Vested	30.34
Forfeited	29.40
Balance, end of year	$ 29.15	$ 31.41

SHARE-BASED COMPENSATION - Weig

SHARE-BASED COMPENSATION - Weighted Average Assumptions Used in Estimating the Value of Performance Share Units (Details) - Performance share units - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Expected dividends	5.25%	3.81%	3.74%
Risk-free rate minimum	2.43%	1.75%	0.68%
Risk-free rate maximum	2.55%	2.34%	1.55%
Volatility minimum	22.50%	17.30%	22.71%
Volatility maximum	27.40%	21.52%	24.07%
Weighted average grant-date fair value	$ 29.66	$ 35.49	$ 37.93
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Performance period	Jan. 1, 2019	Jan. 1, 2018	Jan. 1, 2017
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Performance period	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019

SHARE-BASED COMPENSATION - Sc_2

SHARE-BASED COMPENSATION - Schedule of Performance Share Units Activity (Details) - Performance share units - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Units
Balance, beginning of year	1,042
Granted	419
Vested	(153)
Forfeited	(26)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Performance Adjustment	(233)
Balance, end of year	1,049	1,042
Nonvested performance share units that have met the requisite service period and will be released as identified in the grant terms	519
Weighted Average Grant Date Fair Value
Balance, beginning of year	$ 31.52
Granted	29.66	$ 35.49	$ 37.93
Vested	22.80
Forfeited	34.05
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Performance Adjustment, Weighted Average Grant Date Fair Value	22.80
Balance, end of year	$ 33.93	$ 31.52

SHARE-BASED COMPENSATION - Sc_3

SHARE-BASED COMPENSATION - Schedule of Stock Options Activity (Details) - Stock options $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)$ / sharesshares
Options
Balance, beginning of year	6,366
Exercised	(661)
Forfeited or expired	(430)
Balance, end of year	5,275
Exercisable, end of year	4,678
Number of options outstanding that have met the requisite service period and will be released as identified in the grant terms	324
Weighted Average Exercise Price
Balance, beginning of year | $ / shares	$ 26.75
Exercised | $ / shares	19.16
Forfeited or expired | $ / shares	31.63
Balance, end of year | $ / shares	27.30
Exercisable, end of year | $ / shares	$ 27.84
Weighted Average Remaining Contractual Term
Balance, end of year	4 years 7 months 9 days
Exercisable, end of year	4 years 5 months 1 day
Aggregate Intrinsic Value
Balance, end of year | $	$ 21
Exercisable, end of year | $	$ 17

LEASES Additional Information (

LEASES Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019
Total leased assets	$ 148	$ 165
Total lease liabilities	$ 156	172
Amount recorded to retained earnings related to new accounting pronouncement		$ 7
Minimum
Operating and finance leases remaining lease term	1 year
Maximum
Operating and finance leases remaining lease term	25 years

LEASES Summary of Lease Expense

LEASES Summary of Lease Expense (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Leases [Abstract]
Operating lease costs	$ 20
Financing lease costs	15
Total lease costs	$ 35

LEASES Supplemental Cash Flow I

LEASES Supplemental Cash Flow Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows for operating leases	$ 20
Financing cash flows for financing leases	16
ROU assets obtained in exchange for new (modified) lease liabilities:
Operating leases	6
Financing leases	$ 5

LEASES Supplemental Balance She

LEASES Supplemental Balance Sheet Information Related to Leases (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019
Assets
Operating lease ROU assets	$ 120
Financing lease ROU assets	28
Total leased assets	148	$ 165
Current:
Operating lease liabilities	20
Financing lease liabilities	13
Noncurrent:
Operating lease liabilities	103
Financing lease liabilities	20
Total lease liabilities	$ 156	$ 172

LEASES Lease Term and Discount

LEASES Lease Term and Discount Rate (Details)	Dec. 31, 2019
Weighted Average Remaining Lease Term (years)
Operating lease, weighted average remaining lease term	11 years
Finance lease, weighted average remaining lease term	3 years
Weighted Average Discount Rate
Operating lease, weighted average discount rate	4.20%
Finance lease, weighted average discount rate	3.10%

LEASES Maturities of Lease Liab

LEASES Maturities of Lease Liabilities (Details) $ in Millions	Dec. 31, 2019USD ($)
Operating Lease
Operating lease liability payments of 2020	$ 20
Operating lease liability payments of 2021	18
Operating lease liability payments of 2022	17
Operating lease liability payments of 2023	16
Operating lease liability payments of 2024	12
Operating lease liability payments thereafter	70
Operating lease total payments due	153
Operating lease interest	(30)
Operating lease liability present value	123
Finance Leases
Finance lease liability payments of 2020	14
Finance lease liability payments of 2021	10
Finance lease liability payments of 2022	7
Finance lease liability payments of 2023	4
Finance lease liability payments of 2024	0
Finance lease liability payments thereafter	0
Finance lease total payments due	35
Finance lease interest	(2)
Finance lease liability present value	$ 33

LEASES Operating Lease Commitme

LEASES Operating Lease Commitments (Details) $ in Millions	Dec. 31, 2018USD ($)
Leases [Abstract]
Operating lease commitment due 2019	$ 35
Operating lease commitment due 2020	29
Operating lease commitment due 2021	26
Operating lease commitment due 2022	24
Operating lease commitment due 2023	18
Operating lease commitment due Thereafter	$ 78

CHARGES FOR INTEGRATION AND R_2

CHARGES FOR INTEGRATION AND RESTRUCTURING, CLOSURES AND ASSET IMPAIRMENTS - Additional Information (Details) $ in Millions	Dec. 17, 2019a	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Restructuring Cost And Reserve [Line Items]
Impairment charges		$ 80	$ 80
Asset Impairment Charges			80	$ 1	$ 154
Montana
Restructuring Cost And Reserve [Line Items]
Impairment charges			80
Number of acers of timberlands agreed to be sold | a	630,000
Cash purchase price of assets to be disposed of			145
Timberlands
Restructuring Cost And Reserve [Line Items]
Impairment charges			$ 80
Asset Impairment Charges					147
Plum Creek
Restructuring Cost And Reserve [Line Items]
Total charges for termination benefits					34
Other Closures and Restructuring
Restructuring Cost And Reserve [Line Items]
Total charges for other restructuring and closure costs					$ 6

CHARGES (RECOVERIES) FOR PROD_2

CHARGES (RECOVERIES) FOR PRODUCT REMEDIATION, NET (Details) - Wood Products - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Product Liability Contingency [Line Items]
Insurance recoveries	$ 68	$ 25
Charges (recoveries) for product remediation, net		$ 25	$ 290

OTHER OPERATING COSTS (INCOME_3

OTHER OPERATING COSTS (INCOME), NET - Income and Expense Items Included in Other Operating Costs (Income), Net (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)a
Other Operating Income (Expense) [Line Items]
Environmental remediation insurance recoveries	$ 0	$ (5)	$ (42)
Foreign exchange losses (gains), net	2	(3)	(1)
Gain on disposition of nonstrategic assets	(4)	(5)	(16)
Gain on sale of timberlands	(48)	0	(99)
Litigation expense, net	63	35	20
Research and development expenses	6	8	14
Other, net	28	52	10
Total other operating costs (income), net	$ 47	$ 82	(114)
Twin Creeks
Other Operating Income (Expense) [Line Items]
Gain on sale of timberlands			$ (99)
Sale of timberland acreage | a			100,000

INCOME TAXES - Domestic and For

INCOME TAXES - Domestic and Foreign Earnings (Loss) Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments [Abstract]
Domestic earnings (loss)									$ (268)	$ 556	$ 643
Foreign earnings									55	251	73
Earnings (loss) before income taxes	$ (13)	$ 102	$ 91	$ (393)	$ (114)	$ 240	$ 382	$ 299	$ (213)	$ 807	$ 716

INCOME TAXES - Provision (Benef

INCOME TAXES - Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ 21	$ (69)	$ 10
State	1	(5)	0
Foreign	10	61	82
Total current	32	(13)	92
Deferred:
Federal	(137)	45	61
State	(31)	12	(18)
Foreign	(1)	15	(1)
Total deferred	(169)	72	42
Total income tax provision (benefit)	$ (137)	$ 59	$ 134

INCOME TAXES - Effective Income

INCOME TAXES - Effective Income Tax Rate Applicable (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation [Abstract]
U.S. federal statutory income tax		$ (45)	$ 170	$ 250
State income taxes, net of federal tax benefit		(31)	8	(2)
REIT income not subject to federal income tax		(68)	(116)	(198)
SDT settlement	$ 21	0	21	0
Tax effect of U.S. corporate rate change		0	0	74
Voluntary pension contribution		0	(41)	0
Return to provision adjustment		4	(1)	2
Foreign taxes		(2)	15	54
Repatriation of Canadian earnings		0	0	(22)
Other, net		5	3	(24)
Total income tax provision (benefit)		$ (137)	$ 59	$ 134
Effective income tax rate		64.10%	7.30%	18.80%

INCOME TAXES - Additional Infor

INCOME TAXES - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SDT settlement	$ 21		$ 0	$ 21	$ 0
U.S. federal statutory income tax rate				21.00%	35.00%
Tax effect of U.S. corporate rate change			0	$ 0	$ 74
Tax provision benefit		$ 41
Valuation allowance	$ 61		64	$ 61
Canada
Reinvestment of undistributed earnings percentage from foreign subsidiaries				10.00%
Federal, state and foreign
Net operating loss carryforwards			850
Federal - U.S. REIT
Net operating loss carryforwards			302
Credit carryforwards			$ 7
Federal - U.S. REIT | Minimum
Operating Loss Carryforwards, Expiration Date			Dec. 31, 2034
Tax Credit Carryforward, Expiration Date			Dec. 31, 2027
Federal - U.S. REIT | Maximum
Operating Loss Carryforwards, Expiration Date			Dec. 31, 2036
Tax Credit Carryforward, Expiration Date			Dec. 31, 2028
State and Local Jurisdiction [Member]
Net operating loss carryforwards			$ 548
Operating Loss Carryforwards, Expiration Date			Dec. 31, 2022
Credit carryforwards			$ 67
State and Local Jurisdiction [Member] | With expiration
Credit carryforwards			16
State and Local Jurisdiction [Member] | Without expiration
Credit carryforwards			$ 51
State and Local Jurisdiction [Member] | Minimum
Tax Credit Carryforward, Expiration Date			Dec. 31, 2019
State and Local Jurisdiction [Member] | Maximum
Tax Credit Carryforward, Expiration Date			Dec. 31, 2033
Foreign Tax Authority
Net operating loss carryforwards			$ 0
U.S. Qualified Pension Plans
Payment for Pension Benefits				$ 300

INCOME TAXES - Balance Sheet Cl

INCOME TAXES - Balance Sheet Classification of Deferred Income Tax Assets (Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Assets Liabilities Net [Abstract]
Net noncurrent deferred tax asset	$ 72	$ 15
Net noncurrent deferred tax liability	(6)	(43)
Net deferred tax asset (liability)	$ 66	$ (28)

INCOME TAXES - Items Included i

INCOME TAXES - Items Included in Our Deferred Income Tax Assets (Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Components Of Deferred Tax Assets And Liabilities [Abstract]
Pension and postretirement benefits	$ 159	$ 112
State tax credits	53	51
Depletion	34	41
Excess interest	55	30
Incentive compensation	17	20
Workers compensation	18	18
Net operating loss carryforwards	28	19
Other	101	96
Gross deferred tax assets	465	387
Valuation allowance	(64)	(61)
Net deferred tax assets	401	326
Property, plant and equipment	(224)	(197)
Timber installment notes	(74)	(116)
Other	(37)	(41)
Net deferred tax liabilities	(335)	(354)
Net deferred tax asset (liability)	$ 66	$ (28)

GEOGRAPHIC AREAS - Sales by Geo

GEOGRAPHIC AREAS - Sales by Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 1,548	$ 1,671	$ 1,692	$ 1,643	$ 1,636	$ 1,910	$ 2,065	$ 1,865	$ 6,554	$ 7,476	$ 7,196
U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									5,674	6,365	6,168
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									440	519	472
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									305	410	352
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									90	120	107
Other foreign countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									45	62	97
Export sales from the U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									479	604	545
Export sales from the U.S. | U.S. | Japanese Customers
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									265	338	295
Export sales from the U.S. | U.S. | Chinese Customers
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									85	113	102
Export sales from the U.S. | U.S. | Other Countries Customers
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									$ 129	$ 153	$ 148

GEOGRAPHIC AREAS - Long-Lived A

GEOGRAPHIC AREAS - Long-Lived Assets by Geographic Area (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 14,349	$ 14,998
U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	14,074	14,778
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 275	$ 220

SELECTED QUARTERLY FINANCIAL _3

SELECTED QUARTERLY FINANCIAL INFORMATION (unaudited) - Key Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 1,548	$ 1,671	$ 1,692	$ 1,643	$ 1,636	$ 1,910	$ 2,065	$ 1,865	$ 6,554	$ 7,476	$ 7,196
Operating income	89	202	186	174	177	337	476	404	651	1,394	1,131
Earnings (loss) before income taxes	(13)	102	91	(393)	(114)	240	382	299	(213)	807	716
Net earnings (loss)	$ (14)	$ 99	$ 128	$ (289)	$ (93)	$ 255	$ 317	$ 269	$ (76)	$ 748	$ 582
Basic and diluted net earnings (loss) per share	$ (0.02)	$ 0.13	$ 0.17	$ (0.39)	$ (0.12)	$ 0.34	$ 0.42	$ 0.35	$ (0.10)	$ 0.99
Dividends paid per share	$ 0.34	$ 0.34	$ 0.34	$ 0.34	$ 0.34	$ 0.34	$ 0.32	$ 0.32	$ 1.36	$ 1.32	$ 1.25