ONEOK (OKE) 10-Q 29 Apr 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 20, 2020
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-13643
Entity Registrant Name	ONEOK, Inc.
Entity Incorporation, State or Country Code	OK
Entity Tax Identification Number	73-1520922
Entity Address, Address Line One	100 West Fifth Street,
Entity Address, City or Town	Tulsa,
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	74103
City Area Code	918
Local Phone Number	588-7000
Title of 12(b) Security	Common stock, par value of $0.01
Trading Symbol	OKE
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		413,907,211
Entity Central Index Key	0001039684
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Amendment Flag	false

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues
Revenues	$ 2,136,672	$ 2,779,958
Cost of sales and fuel (exclusive of items shown separately below)	1,276,928	1,956,377
Operations and maintenance	175,096	207,251
Depreciation and amortization	132,353	114,158
Impairment charges (Note A)	604,024	0
General taxes	31,944	33,490
Gain on sale of assets	(204)	(60)
Operating income (loss)	(83,469)	468,742
Equity in net earnings from investments (Note I)	44,627	43,481
Impairment of equity investments (Note A)	(37,730)	0
Allowance for equity funds used during construction	15,409	12,441
Other income	8,522	9,360
Other expense	(3,995)	(3,462)
Interest expense (net of capitalized interest of $30,875 and $19,192, respectively)	(140,616)	(115,420)
Income (loss) before income taxes	(197,252)	415,142
Income tax expense (benefit)	55,395	(77,934)
Net income (loss)	(141,857)	337,208
Less: Preferred stock dividends	275	275
Net income (loss) available to common shareholders	$ (142,132)	$ 336,933
Basic earnings (loss) per common share (Note G)	$ (0.34)	$ 0.82
Diluted earnings (loss) per common share (Note G)	$ (0.34)	$ 0.81
Average shares (thousands)
Basic	414,282	412,908
Diluted	415,348	415,233
Commodity Sales
Revenues
Revenues	$ 1,808,620	$ 2,472,959
Services
Revenues
Revenues	$ 328,052	$ 306,999

CONSOLIDATED STATEMENT OF INCOM

CONSOLIDATED STATEMENT OF INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Interest expense (net of capitalized interest)	$ 30,875	$ 19,192

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net income (loss)	$ (141,857)	$ 337,208
Other comprehensive income (loss), net of tax
Change in fair value of derivatives, net of tax of $31,705 and $20,593, respectively	(106,141)	(68,944)
Derivative amounts reclassified to net income (loss), net of tax of $4,518 and $4,177, respectively	(15,164)	(12,171)
Change in retirement and other postretirement benefit plan obligations, net of tax of $(1,064) and $(699), respectively	3,562	2,341
Other comprehensive income (loss) of unconsolidated affiliates, net of tax of $2,283 and $750, respectively	(7,643)	(2,511)
Total other comprehensive income (loss), net of tax	(125,386)	(81,285)
Comprehensive income (loss)	$ (267,243)	$ 255,923

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (PARANTHETICAL) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Change in fair value of derivatives, tax	$ 31,705	$ 20,593
Derivative amounts reclassified to net income (loss), tax	4,518	4,177
Change in retirement and other postretirement benefit plan obligations, tax	(1,064)	(699)
Other comprehensive income (loss) on investments in unconsolidated affiliates, tax	$ 2,283	$ 750

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 531,630	$ 20,958
Accounts receivable, net	497,556	835,121
Materials and supplies	255,071	201,749
NGLs and natural gas in storage	131,041	304,926
Commodity imbalances	13,868	25,267
Other current assets	59,116	82,313
Total current assets	1,488,282	1,470,334
Property, plant and equipment
Property, plant and equipment	22,136,442	22,051,492
Accumulated depreciation and amortization	3,506,950	3,702,807
Net property, plant and equipment	18,629,492	18,348,685
Investments and other assets
Investments in unconsolidated affiliates (Note A)	810,479	861,844
Goodwill and intangible assets (Note A)	781,544	957,833
Other assets	259,643	173,425
Total investments and other assets	1,851,666	1,993,102
Total assets	21,969,440	21,812,121
Current liabilities
Current maturities of long-term debt (Note D)	7,650	7,650
Short-term borrowings (Note D)	0	220,000
Accounts payable	742,369	1,209,900
Commodity imbalances	55,162	104,480
Accrued taxes	61,057	75,422
Accrued interest	121,832	190,750
Operating lease liability, current	13,425	1,883
Other current liabilities	89,897	210,213
Total current liabilities	1,091,392	2,020,298
Long-term debt, excluding current maturities (Note D)	14,146,650	12,479,757
Deferred credits and other liabilities
Deferred income taxes	442,653	536,063
Operating lease liability, noncurrent	96,431	13,509
Other deferred credits	631,673	536,543
Total deferred credits and other liabilities	1,170,757	1,086,115
Commitments and contingencies (Note J)
Equity (Note E)
Preferred stock, $0.01 par value: authorized and issued 20,000 shares at March 31, 2020, and December 31, 2019	0	0
Common stock, $0.01 par value: authorized 1,200,000,000 shares, issued 445,016,234 shares and outstanding 413,882,720 shares at March 31, 2020; issued 445,016,234 shares and outstanding 413,239,050 shares at December 31, 2019	4,450	4,450
Paid-in capital	6,989,453	7,403,895
Accumulated other comprehensive loss (Note F)	(499,386)	(374,000)
Retained earnings (accumulated deficit)	(141,857)	0
Treasury stock, at cost: 31,133,514 shares at March 31, 2020, and 31,777,184 shares at December 31, 2019	(792,019)	(808,394)
Total equity	5,560,641	6,225,951
Total liabilities and equity	$ 21,969,440	$ 21,812,121

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
Equity (Note E)
Common stock, shares, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares, authorized (in shares)	1,200,000,000	1,200,000,000
Common stock, shares, issued (in shares)	445,016,234	445,016,234
Common stock, shares, outstanding (in shares)	413,882,720	413,239,050
Treasury stock, shares (in shares)	31,133,514	31,777,184
Preferred stock, shares, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares, issued (in shares)	20,000	20,000

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating activities
Net income (loss)	$ (141,857)	$ 337,208
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	132,353	114,158
Impairment charges	641,754	0
Equity in net earnings from investments	(44,627)	(43,481)
Distributions received from unconsolidated affiliates	41,577	45,936
Deferred income tax expense (benefit)	(55,949)	75,994
Other, net	(30,380)	(16,144)
Changes in assets and liabilities:
Accounts receivable	334,370	6,089
NGLs and natural gas in storage	173,885	53,444
Accounts payable	(350,701)	(62,469)
Accrued interest	(68,918)	(47,810)
Risk-management assets and liabilities	(78,856)	4,362
Other assets and liabilities, net	(129,930)	(113,681)
Cash provided by operating activities	422,721	353,606
Investing activities
Capital expenditures (less allowance for equity funds used during construction)	(949,679)	(889,705)
Distributions received from unconsolidated affiliates in excess of cumulative earnings	6,949	13,527
Other, net	(22,062)	11,349
Cash used in investing activities	(964,792)	(864,829)
Financing activities
Dividends paid	(386,667)	(354,203)
Repayment of short-term borrowings, net	(220,000)	0
Issuance of long-term debt, net of discounts	1,748,221	1,442,782
Debt financing costs	(15,444)	(11,663)
Repayment of long-term debt	(52,389)	(501,913)
Other, net	(20,978)	(47,941)
Cash provided by financing activities	1,052,743	527,062
Change in cash and cash equivalents	510,672	15,839
Cash and cash equivalents at beginning of period	20,958	11,975
Cash and cash equivalents at end of period	$ 531,630	$ 27,814

CONSOLIDATED STATEMENT OF CHANG

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Common Stock	Preferred Stock	Accumulated Other Comprehensive Loss	Retained Earnings (Accumulated Deficit)	Paid-in Capital	Treasury Stock	Noncontrolling Interest [Member]
Shares, issued, beginning balance at Dec. 31, 2018		445,016,234	20,000
Total equity, beginning balance at Dec. 31, 2018		$ 4,450	$ 0	$ (188,239)	$ 0	$ 7,615,138	$ (851,806)	$ 6,579,543
Net income (loss)	$ 337,208	0	0	0	337,208	0	0
Other comprehensive loss	(81,285)	0	0	(81,285)	0	0	0
Preferred stock dividends	(275)	0	0	0	(275)	0	0
Common Stock Issued During Period, Value, Other	6,260	0	0	0	0	(24,779)	31,039
Common Stock Dividends	(354,304)	0	0	0	(336,866)	(17,438)	0
Other, net	(45,074)	$ 0	$ 0	0	0	(45,074)	0
Shares, issued, ending balance at Mar. 31, 2019		445,016,234	20,000
Total equity, ending balance at Mar. 31, 2019		$ 4,450	$ 0	(269,524)	0	7,527,847	(820,767)	$ 6,442,006
Cumulative effect adjustment for adoption of ASU 2016-02, “Leases (Topic 842)”	(67)	$ 0	$ 0	0	(67)	0	0
Shares, issued, beginning balance at Dec. 31, 2019		445,016,234	20,000
Total equity, beginning balance at Dec. 31, 2019	6,225,951	$ 4,450	$ 0	(374,000)	0	7,403,895	(808,394)
Net income (loss)	(141,857)	0	0	0	(141,857)	0	0
Other comprehensive loss	(125,386)	0	0	(125,386)	0	0	0
Preferred stock dividends	(275)	$ 0	0	0	0	(275)	0
Common Stock Issued During Period, Shares, Other		0
Common Stock Issued During Period, Value, Other	7,089	$ 0	0	0	0	(9,286)	16,375
Common Stock Dividends	(386,931)	0	0	0	0	(386,931)	0
Other, net	(17,950)	$ 0	$ 0	0	0	(17,950)	0
Shares, issued, ending balance at Mar. 31, 2020		445,016,234	20,000
Total equity, ending balance at Mar. 31, 2020	$ 5,560,641	$ 4,450	$ 0	$ (499,386)	$ (141,857)	$ 6,989,453	$ (792,019)

CONSOLIDATED STATEMENT OF CHA_2

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY CONSOLIDATED STATEMENT OF CHANGES IN EQUITY Parenthetical - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Stockholders' Equity [Abstract]
Preferred stock, dividends paid (in dollars per share)	$ 13.75	$ 13.75
Dividends paid (in dollars per share)	$ 0.935	$ 0.86

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Notes)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Our accompanying unaudited Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the SEC. These statements have been prepared in accordance with GAAP and reflect all adjustments that, in our opinion, are necessary for a fair statement of the results for the interim periods presented. All such adjustments are of a normal recurring nature. The 2019 year-end Consolidated Balance Sheet data was derived from our audited Consolidated Financial Statements but does not include all disclosures required by GAAP. Certain reclassifications have been made in the prior-year Consolidated Financial Statements to conform to the current year presentation. These unaudited Consolidated Financial Statements should be read in conjunction with our audited Consolidated Financial Statements in our Annual Report. In March 2020, the CARES Act was signed into law in response to the COVID-19 pandemic, and we opted into the CARES Act 401(k) hardship withdrawal and loan deferral programs for employees. While this legislation includes tax provisions that will modestly benefit us, we do not expect the CARES Act to materially impact us. Impairment Charges - Late in the first quarter 2020, we experienced a significant decline in our share price and market capitalization as the energy industry experienced historic events that led to a simultaneous demand and supply shock. The World Health Organization declared the novel strain of COVID-19 a global pandemic and recommended containment and mitigation measures worldwide, which contributed to a massive economic slowdown and decreased demand for crude oil. In addition, Saudi Arabia and Russia increased production of crude oil as the two countries competed for market share. As a result, the global supply of crude oil significantly exceeded demand and led to a collapse in crude oil prices. Despite recently announced production cuts from many oil producing countries, supply exceeds demand, crude oil storage is near capacity and prices remain volatile. The collapse in crude oil prices and demand for energy commodities have also contributed to lower NGL product prices and lower natural gas prices, which is creating challenges for crude oil and natural gas producers as they assess their future drilling and production plans. Based on these events, we performed a Step 1 analysis to test our goodwill for impairment and evaluated certain long-lived asset groups and equity investments for impairment. Goodwill - We assess our goodwill for impairment at least annually on July 1, unless events or changes in circumstances indicate an impairment may have occurred before that time. In the Step 1 analysis, an assessment is made by comparing the fair value of a reporting unit with its carrying amount, including goodwill. If the carrying value of a reporting unit exceeds its fair value, an impairment loss is recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit. In January 2020, we adopted ASU 2017-04, in which the requirement to calculate the implied fair value of goodwill under the two-step impairment test was eliminated. To estimate the fair value of our reporting units, we use two generally accepted valuation approaches, an income approach and a market approach, using assumptions consistent with a market participant’s perspective. Under the income approach, we use anticipated cash flows over a period of years plus a terminal value and discount these amounts to their present value using appropriate discount rates. Under the market approach, we apply EBITDA multiples to forecasted EBITDA. The multiples used are consistent with historical asset transactions. The forecasted cash flows are based on average forecasted cash flows for a reporting unit over a period of years. Based on the results of our impairment test, we concluded the carrying value of the Natural Gas Gathering and Processing reporting unit exceeded its estimated fair value, resulting in a noncash impairment charge of $153.4 million for the three months ended March 31, 2020, which is included within impairment charges in our Consolidated Statement of Income. The estimated fair value of our Natural Gas Liquids and Natural Gas Pipelines reporting units substantially exceeded their respective carrying values. The following table sets forth our goodwill, by segment, for the periods indicated: March 31, December 31, ( Thousands of dollars ) Natural Gas Gathering and Processing $ — $ 153,404 Natural Gas Liquids 371,217 371,217 Natural Gas Pipelines 156,375 156,375 Total goodwill $ 527,592 $ 680,996 Long-lived assets - We assess our long-lived assets for impairment whenever events or changes in circumstances indicate that an asset’s carrying amount may not be recoverable. An impairment is indicated if the carrying amount of a long-lived asset exceeds the sum of the undiscounted future cash flows expected to result from the use and eventual disposition of the asset. If an impairment is indicated, we record an impairment loss equal to the difference between the carrying value and the fair value of the long-lived asset. We evaluated our Natural Gas Gathering and Processing segment asset groups and determined that the carrying value of certain long-lived asset groups in western Oklahoma, Kansas and the Powder River Basin, where lower pricing is expected to impact drilling and production levels, are not recoverable and exceeded their estimated fair value. We recorded noncash impairment charges of $380.5 million for the three months ended March 31, 2020, which includes impairment to intangible assets of $19.9 million related to supply contracts. In our Natural Gas Liquids segment, we recorded noncash impairment charges of $70.2 million for the three months ended March 31, 2020, related to certain inactive assets, as our expectation for future use of the assets changed. These charges are included within impairment charges in our Consolidated Statement of Income. Investments in unconsolidated affiliates - The impairment test for equity-method investments considers whether the fair value of the equity investment as a whole, not the underlying net assets, has declined and whether that decline is other than temporary. Therefore, we periodically evaluate the amount at which we carry our equity-method investments to determine whether current events or circumstances warrant adjustments to our carrying values. We evaluated our investments in unconsolidated affiliates and concluded that the carrying value of our 10.2% investment in Venice Energy Services Company in our Natural Gas Gathering and Processing segment exceeded its estimated fair value, resulting in a noncash impairment charge of $30.5 million for the three months ended March 31, 2020, which includes an impairment to our equity-method goodwill of $22.3 million . We also concluded that the carrying value of our 50% investment in Chisholm Pipeline Company in our Natural Gas Liquids segment exceeded its estimated fair value, resulting in a noncash impairment charge of $7.2 million for the three months ended March 31, 2020. These impairment charges are included within impairment of equity investments in our Consolidated Statement of Income. Recently Issued Accounting Standards Update - Changes to GAAP are established by the Financial Accounting Standards Board (FASB) in the form of ASUs to the FASB Accounting Standards Codification. We consider the applicability and impact of all ASUs. ASUs not listed below or in our Annual Report were assessed and determined to be either not applicable or clarifications of ASUs previously issued or listed below. Except as discussed below or in our Annual Report, there have been no new accounting pronouncements that have become effective or have been issued that are of significance or potential significance to us. The following table provides a brief description of recently adopted accounting pronouncements and our analysis of the effects on our financial statements: Standard Description Date of Adoption Effect on the Financial Statements or Other Significant Matters ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” The standard requires a financial asset (or a group of financial assets) measured at amortized cost basis to be presented net of the allowance for credit losses to reflect the net carrying value at the amount expected to be collected on the financial asset; and the initial allowance for credit losses for purchased financial assets, including available-for-sale debt securities, to be added to the purchase price rather than being reported as a credit loss expense. First quarter 2020 The impact of adopting this standard was not material. ASU 2017-04, “Intangibles- Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” The standard simplifies the subsequent measurement of goodwill by eliminating the requirement to calculate the implied fair value of goodwill under step 2. Instead, an entity will recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. The standard does not change step zero or step 1 assessments. First quarter 2020 We adopted and implemented this standard to record noncash impairment charges related to our goodwill, as described above. ASU 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting” The standard provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. First quarter 2020 The impact of adopting this standard was not material.

FAIR VALUE MEASUREMENTS (Notes)

FAIR VALUE MEASUREMENTS (Notes)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Determining Fair Value - For our fair value measurements, we utilize market prices, third-party pricing services, present value methods and standard option valuation models to determine the price we would receive from the sale of an asset or the transfer of a liability in an orderly transaction at the measurement date. We measure the fair value of a group of financial assets and liabilities consistent with how a market participant would price the net risk exposure at the measurement date. Many of the contracts in our derivative portfolio are executed in liquid markets where price transparency exists. Our financial commodity derivatives are generally settled through a NYMEX or Intercontinental Exchange (ICE) clearing broker account with daily margin requirements. We validate our valuation inputs with third-party information and settlement prices from other sources, where available. We compute the fair value of our derivative portfolio by discounting the projected future cash flows from our derivative assets and liabilities to present value using interest-rate yields to calculate present-value discount factors derived from the implied forward LIBOR yield curve. The fair value of our forward-starting interest-rate swaps is determined using financial models that incorporate the implied forward LIBOR yield curve for the same period as the future interest-rate swap settlements. We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using counterparty-specific bond yields. Although we use our best estimates to determine the fair value of the derivative contracts we have executed, the ultimate market prices realized could differ materially from our estimates. Fair Value Hierarchy - At each balance sheet date, we utilize a fair value hierarchy to classify fair value amounts recognized or disclosed in our financial statements based on the observability of inputs used to estimate such fair value. The levels of the hierarchy are described below: • Level 1 - fair value measurements are based on unadjusted quoted prices for identical securities in active markets. These balances are composed predominantly of exchange-traded derivative contracts for natural gas and crude oil. • Level 2 - fair value measurements are based on significant observable pricing inputs, including quoted prices for similar assets and liabilities in active markets and inputs from third-party pricing services supported with corroborative evidence. These balances are composed of over-the-counter interest-rate derivatives. • Level 3 - fair value measurements are based on inputs that may include one or more unobservable inputs, including internally developed commodity price curves that incorporate market data from broker quotes and third-party pricing services. These balances are composed predominantly of exchange-cleared and over-the-counter derivatives to hedge NGL price risk and natural gas basis risk between various transaction locations and the NYMEX Henry Hub. Our commodity derivatives are generally valued using forward quotes provided by third-party pricing services that are validated with other market data. We believe any measurement uncertainty at March 31, 2020, is immaterial as our Level 3 fair value measurements are based on unadjusted pricing information from broker quotes and third-party pricing services. We do not believe that our Level 3 fair value estimates have a material impact on our results of operations, as our derivatives are accounted for as hedges. Determining the appropriate classification of our fair value measurements within the fair value hierarchy requires management’s judgment regarding the degree to which market data is observable or corroborated by observable market data. We categorize derivatives for which fair value is determined using multiple inputs within a single level, based on the lowest level input that is significant to the fair value measurement in its entirety. Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements for the periods indicated: March 31, 2020 Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net ( Thousands of dollars ) Derivative assets Commodity contracts Financial contracts $ 37,599 $ — $ 130,272 $ 167,871 $ (140,707 ) $ 27,164 Total derivative assets $ 37,599 $ — $ 130,272 $ 167,871 $ (140,707 ) $ 27,164 Derivative liabilities Commodity contracts Financial contracts $ (911 ) $ — $ (72,871 ) $ (73,783 ) $ 73,783 $ — Interest-rate contracts — (270,297 ) — (270,297 ) — (270,297 ) Total derivative liabilities $ (911 ) $ (270,297 ) $ (72,871 ) $ (344,080 ) $ 73,783 $ (270,297 ) (a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheet on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At March 31, 2020 , we posted no cash and held cash of $66.9 million from various counterparties, which offsets our derivative net asset position under master netting arrangements as shown in the table above. December 31, 2019 Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net ( Thousands of dollars ) Derivative assets Commodity contracts Financial contracts $ 10,892 $ — $ 55,557 $ 66,449 $ (28,588 ) $ 37,861 Interest-rate contracts — 581 — 581 — 581 Total derivative assets $ 10,892 $ 581 $ 55,557 $ 67,030 $ (28,588 ) $ 38,442 Derivative liabilities Commodity contracts Financial contracts $ (4,811 ) $ — $ (24,785 ) $ (29,596 ) $ 28,588 $ (1,008 ) Interest-rate contracts — (201,941 ) — (201,941 ) — (201,941 ) Total derivative liabilities $ (4,811 ) $ (201,941 ) $ (24,785 ) $ (231,537 ) $ 28,588 $ (202,949 ) (a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheet on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2019 , we held no cash and posted $8.8 million of cash with various counterparties, which is included in other current assets in our Consolidated Balance Sheet. The following table sets forth a reconciliation of our Level 3 fair value measurements for the periods indicated: Three Months Ended March 31, Derivative Assets (Liabilities) 2020 2019 ( Thousands of dollars ) Net assets at beginning of period $ 30,772 $ 40,484 Total changes in fair value: Settlements included in net income (loss) (a) (16,146 ) (25,361 ) New Level 3 derivatives included in other comprehensive income (loss) (b) 20,993 1,597 Unrealized change included in other comprehensive income (loss) (b) 21,782 (5,191 ) Net assets at end of period $ 57,401 $ 11,529 (a) - Included in commodity sales revenues/cost of sales and fuel in our Consolidated Statements of Income. (b) - Included in change in fair value of derivatives in our Consolidated Statements of Comprehensive Income. During the three months ended March 31, 2020 and 2019 , there were no transfers in or out of Level 3 of the fair value hierarchy. Other Financial Instruments - The approximate fair value of cash and cash equivalents, accounts receivable, accounts payable and short-term borrowings is equal to book value due to the short-term nature of these items. Our cash and cash equivalents are composed of bank and money market accounts and are classified as Level 1. Our short-term borrowings are classified as Level 2 since the estimated fair value of the short-term borrowings can be determined using information available in the commercial paper market. The estimated fair value of our consolidated long-term debt, including current maturities, was $11.9 billion and $13.8 billion at March 31, 2020 , and December 31, 2019 , respectively. The book value of our consolidated long-term debt, including current maturities, was $ 14.2 billion and $12.5 billion at March 31, 2020 , and December 31, 2019 , respectively. The estimated fair value of the aggregate long-term debt outstanding was determined using quoted market prices for similar issues with similar terms and maturities. The estimated fair value of our consolidated long-term debt is classified as Level 2. Nonrecurring Fair Value Measurements - During the three months ended March 31, 2020, we recorded noncash impairment charges for certain long-lived assets and equity investments. The valuation of these assets and investments required the use of significant unobservable inputs. To estimate the fair value, we used two generally accepted valuation approaches, an income approach and a market approach. Under the income approach, our discounted cash flow analysis included the following inputs that are not readily available: a discount rate reflective of industry cost of capital, our estimated contract rates, volumes, operating and maintenance costs and capital expenditures. Under the market approach, our inputs included EBITDA multiples and forecasted EBITDA, which was estimated using commodity price forecasts consistent with third-party pricing services. The estimated fair value of these assets is classified as Level 3. See Note A for additional information about our impairment charges.

RISK MANAGEMENT AND HEDGING ACT

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES (Notes)	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES	RISK-MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES Risk-Management Activities - We are sensitive to changes in natural gas, crude oil and NGL prices, principally as a result of contractual terms under which these commodities are processed, purchased and sold. We are also subject to the risk of interest-rate fluctuation in the normal course of business. We use physical-forward purchases and sales and financial derivatives to secure a certain price for a portion of our natural gas, condensate and NGL products; to reduce our exposure to commodity price and interest-rate fluctuations; and to achieve more predictable cash flows. We follow established policies and procedures to assess risk and approve, monitor and report our risk-management activities. We have not used these instruments for trading purposes. Commodity price risk - Commodity price risk refers to the risk of loss in cash flows and future earnings arising from adverse changes in the price of natural gas, NGLs and condensate. We may use the following commodity derivative instruments to reduce the near-term commodity price risk associated with a portion of the forecasted sales of these commodities: • Futures contracts - Standardized contracts to purchase or sell natural gas and crude oil for future delivery or settlement under the provisions of exchange regulations; • Forward contracts - Nonstandardized commitments between two parties to purchase or sell natural gas, crude oil or NGLs for future physical delivery. These contracts are typically nontransferable and can only be canceled with the consent of both parties; • Swaps - Exchange of one or more payments based on the value of one or more commodities. These instruments transfer the financial risk associated with a future change in value between the counterparties of the transaction, without also conveying ownership interest in the asset or liability; and • Options - Contractual agreements that give the holder the right, but not the obligation, to buy or sell a fixed quantity of a commodity at a fixed price within a specified period of time. Options may either be standardized and exchange-traded or customized and nonexchange-traded. We may also use other instruments including collars to mitigate commodity price risk. A collar is a combination of a purchased put option and a sold call option, which places a floor and a ceiling price for commodity sales being hedged. In our Natural Gas Gathering and Processing segment, we are exposed to commodity price risk as a result of retaining a portion of the commodity sales proceeds associated with our POP with fee contracts. Under certain POP with fee contracts, our fees and POP percentage may increase or decrease if production volumes, delivery pressures or commodity prices change relative to specified thresholds. We also are exposed to basis risk between the various production and market locations where we buy and sell commodities. As part of our hedging strategy, we use the previously described commodity derivative financial instruments and physical-forward contracts to reduce the impact of price fluctuations related to natural gas, NGLs and condensate. In our Natural Gas Liquids segment, we are primarily exposed to commodity price risk resulting from the relative values of the various NGL products to each other, the value of NGLs in storage and the relative value of NGLs to natural gas. We are also exposed to location price differential risk as a result of the relative value of NGL purchases at one location and sales at another location, primarily related to our optimization and marketing activities. As part of our hedging strategy, we utilize physical-forward contracts and commodity derivative financial instruments to reduce the impact of price fluctuations related to NGLs. In our Natural Gas Pipelines segment, we are primarily exposed to commodity price risk on our intrastate pipelines because they consume natural gas in operations and retain natural gas from our customers for operations or as part of our fee for services provided. When the amount consumed in operations differs from the amount provided by our customers, our pipelines must buy or sell natural gas, or store or use natural gas from inventory, which can expose this segment to commodity price risk depending on the regulatory treatment for this activity. To the extent that commodity price risk in our Natural Gas Pipelines segment is not mitigated by fuel cost-recovery mechanisms, we may use physical-forward sales or purchases to reduce the impact of natural gas price fluctuations. At March 31, 2020 , and December 31, 2019 , there were no financial derivative instruments with respect to our natural gas pipeline operations. Interest-rate risk - We manage interest-rate risk through the use of fixed-rate debt, floating-rate debt and interest-rate swaps. Interest-rate swaps are agreements to exchange interest payments at some future point based on specified notional amounts. In March 2020, we settled $750 million of our forward-starting interest-rate swaps related to our underwritten public offerings of $1.75 billion senior unsecured notes. At March 31, 2020 , and December 31, 2019 , we had forward-starting interest-rate swaps with notional amounts totaling $1.1 billion and $1.8 billion , respectively, to hedge the variability of interest payments on a portion of our forecasted debt issuances. At March 31, 2020 , and December 31, 2019 , we had interest-rate swaps with notional amounts totaling $1.3 billion to hedge the variability of our LIBOR-based interest payments. All of our interest-rate swaps are designated as cash flow hedges. Accounting Treatment - Our accounting treatment of derivative instruments is consistent with that disclosed in Note A of the Notes to Consolidated Financial Statements in our Annual Report. Fair Values of Derivative Instruments - All derivatives measured at fair value at March 31, 2020, and December 31, 2019, were designated as hedging instruments. See Note B for a discussion of the inputs associated with our fair value measurements. The following table sets forth the fair values of our derivative instruments presented on a gross basis for the periods indicated: March 31, 2020 December 31, 2019 Location in our Consolidated Balance Sheets Assets (Liabilities) Assets (Liabilities) ( Thousands of dollars ) Commodity contracts (a) Financial contracts Other current assets $ 167,871 $ (73,783 ) $ 64,858 $ (26,997 ) Other deferred credits — — 1,591 (2,599 ) Interest-rate contracts Other current liabilities — (28,673 ) — (90,161 ) Other assets/other deferred credits — (241,624 ) 581 (111,780 ) Total derivative instruments $ 167,871 $ (344,080 ) $ 67,030 $ (231,537 ) (a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for derivative instruments held for the periods indicated: March 31, 2020 December 31, 2019 Contract Type Purchased/ Payor Sold/ Receiver Purchased/ Payor Sold/ Receiver Cash flow hedges Fixed price - Natural gas ( Bcf ) Futures and swaps — (47.6 ) — (59.0 ) - Crude oil and NGLs ( MMBbl ) Futures, forwards and swaps 10.5 (17.5 ) 7.9 (17.4 ) Basis - Natural gas ( Bcf ) Futures and swaps — (47.6 ) — (59.0 ) Interest-rate contracts ( Billions of dollars ) Swaps $ 2.4 $ — $ 3.1 $ — These notional amounts are used to summarize the volume of financial instruments; however, they do not reflect the extent to which the positions offset one another and, consequently, do not reflect our actual exposure to market or credit risk. Cash Flow Hedges - The following table sets forth the unrealized change in fair value of cash flow hedges in other comprehensive income (loss) for the periods indicated: Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Commodity contracts $ 87,195 $ (21,625 ) Interest-rate contracts (225,041 ) (67,912 ) Total unrealized change in fair value of cash flow hedges in other comprehensive income (loss) $ (137,846 ) $ (89,537 ) The following table sets forth the effect of cash flow hedges on net income (loss) for the periods indicated: Location of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income (Loss) Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Commodity contracts Commodity sales revenues $ 44,999 $ 23,822 Cost of sales and fuel (15,039 ) (4,970 ) Interest-rate contracts Interest expense (10,278 ) (2,504 ) Total change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income (loss) on derivatives $ 19,682 $ 16,348 Credit Risk - We monitor the creditworthiness of our counterparties and compliance with policies and limits established by our Risk Oversight and Strategy Committee. We maintain credit policies with regard to our counterparties that we believe minimize overall credit risk. These policies include an evaluation of potential counterparties’ financial condition (including credit ratings, bond yields and credit default swap rates), collateral requirements under certain circumstances and the use of standardized master-netting agreements that allow us to net the positive and negative exposures associated with a single counterparty. We use internally developed credit ratings for counterparties that do not have a credit rating. Our financial commodity derivatives are generally settled through a NYMEX or Intercontinental Exchange (ICE) clearing broker account with daily margin requirements. However, we may enter into financial derivative instruments that contain provisions that require us to maintain an investment-grade credit rating from S&P and/or Moody’s. If our credit ratings on our senior unsecured long-term debt were to decline below investment grade, the counterparties to the derivative instruments could request collateralization on derivative instruments in net liability positions. There were no financial derivative instruments with contingent features related to credit risk at March 31, 2020 . The counterparties to our derivative contracts typically consist of major energy companies, financial institutions and commercial and industrial end users. This concentration of counterparties may affect our overall exposure to credit risk, either positively or negatively, in that the counterparties may be affected similarly by changes in economic, regulatory or other conditions. Based on our policies, exposures, credit and other reserves, we do not anticipate a material adverse effect on our financial position or results of operations as a result of counterparty nonperformance. At March 31, 2020 , the credit exposure from our derivative assets is with investment-grade companies in the financial services sector.

DEBT DEBT (Notes)

DEBT DEBT (Notes)	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Debt [Text Block]	DEBT The following table sets forth our consolidated debt for the periods indicated: March 31, December 31, ( Thousands of dollars ) Commercial paper outstanding, bearing a weighted-average interest rate of 2.16% as of December 31, 2019 $ — $ 220,000 Senior unsecured obligations: $1,500,000 term loan, variable rate, due November 2021 1,250,000 1,250,000 $700,000 at 4.25% due February 2022 547,397 547,397 $900,000 at 3.375% due October 2022 900,000 900,000 $425,000 at 5.0% due September 2023 425,000 425,000 $500,000 at 7.5% due September 2023 500,000 500,000 $500,000 at 2.75% due September 2024 500,000 500,000 $500,000 at 4.9% due March 2025 500,000 500,000 $400,000 at 2.2% due September 2025 397,000 — $500,000 at 4.0% due July 2027 500,000 500,000 $800,000 at 4.55% due July 2028 800,000 800,000 $100,000 at 6.875% due September 2028 100,000 100,000 $700,000 at 4.35% due March 2029 700,000 700,000 $750,000 at 3.4% due September 2029 734,251 750,000 $850,000 at 3.1% due March 2030 821,050 — $400,000 at 6.0% due June 2035 400,000 400,000 $600,000 at 6.65% due October 2036 600,000 600,000 $600,000 at 6.85% due October 2037 600,000 600,000 $650,000 at 6.125% due February 2041 650,000 650,000 $400,000 at 6.2% due September 2043 400,000 400,000 $700,000 at 4.95% due July 2047 693,405 700,000 $1,000,000 at 5.2% due July 2048 1,000,000 1,000,000 $750,000 at 4.45% due September 2049 747,650 750,000 $500,000 at 4.5% due March 2050 489,625 — Guardian Pipeline Weighted average 7.85% due December 2022 19,395 21,307 Total debt 14,274,773 12,813,704 Unamortized portion of terminated swaps 14,603 15,032 Unamortized debt issuance costs and discounts (135,076 ) (121,329 ) Current maturities of long-term debt (7,650 ) (7,650 ) Short-term borrowings (a) — (220,000 ) Long-term debt $ 14,146,650 $ 12,479,757 (a) - Individual issuances of commercial paper under our commercial paper program generally mature in 90 days or less. $2.5 Billion Credit Agreement - Our $2.5 Billion Credit Agreement is a revolving credit facility and contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in our $2.5 Billion Credit Agreement, adjusted for all noncash charges and increased for projected EBITDA from certain lender-approved capital expansion projects) of no more than 5.0 to 1 at March 31, 2020. At March 31, 2020 , we had no borrowings outstanding, our ratio of indebtedness to adjusted EBITDA was 4.5 to 1, and we were in compliance with all covenants under our $2.5 Billion Credit Agreement. Debt Issuances - In early March 2020, we completed an underwritten public offering of $1.75 billion senior unsecured notes consisting of $400 million , 2.2% senior notes due 2025; $850 million , 3.1% senior notes due 2030; and $500 million , 4.5% senior notes due 2050. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $1.73 billion . A portion of the proceeds were used to pay all outstanding amounts under our commercial paper program. The remainder was, and will be, used for general corporate purposes, which may include repayment of other existing indebtedness and funding capital expenditures. Debt Repayments - In March 2020, we repurchased in the open market $67.0 million outstanding principal of certain of our senior notes for an aggregate repurchase price of $50.5 million with cash on hand. In connection with these open market repurchases, we recognized a $15.8 million gain on extinguishment of debt, which is included in other income in our Consolidated Statement of Income for the three months ended March 31, 2020. Debt Guarantees - We, ONEOK Partners and the Intermediate Partnership have cross guarantees in place for our and ONEOK Partners’ indebtedness. For additional discussion of our $2.5 Billion Credit Agreement and our $1.5 Billion Term Loan Agreement, see Note F of the Notes to Consolidated Financial Statements in our Annual Report.

EQUITY (Notes)

EQUITY (Notes)	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
EQUITY	EQUITY Dividends - Holders of our common stock share equally in any dividend declared by our Board of Directors, subject to the rights of the holders of outstanding preferred stock. Dividends paid on our common stock in February 2020 were $0.935 per share. A dividend of $0.935 per share was declared for shareholders of record at the close of business on April 27, 2020 , payable May 14, 2020 . The Series E Preferred Stock pays quarterly dividends on each share of Series E Preferred Stock, when, as and if declared by our Board of Directors, at a rate of 5.5% per year. We paid dividends for the Series E Preferred Stock of $0.3 million in February 2020. Dividends totaling $0.3 million were declared for the Series E Preferred Stock and are payable May 14, 2020 .

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Notes)	3 Months Ended
	Mar. 31, 2020
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS The following table sets forth the balance in accumulated other comprehensive loss for the period indicated: Risk- Management Assets/Liabilities (a) Retirement and Other Postretirement Benefit Plan Obligations (a) (b) Risk- Management Assets/Liabilities of Unconsolidated Affiliates (a) Accumulated Other Comprehensive Loss (a) ( Thousands of dollars ) January 1, 2020 $ (233,520 ) $ (131,481 ) $ (8,999 ) $ (374,000 ) Other comprehensive income (loss) before reclassifications (106,141 ) 20 (7,777 ) (113,898 ) Amounts reclassified to net income (loss) (c) (15,164 ) 3,542 134 (11,488 ) Other comprehensive income (loss) (121,305 ) 3,562 (7,643 ) (125,386 ) March 31, 2020 $ (354,825 ) $ (127,919 ) $ (16,642 ) $ (499,386 ) (a) - All amounts are presented net of tax. (b) - Includes amounts related to supplemental executive retirement plan. (c) - See Note C for details of amounts reclassified to net income (loss) for risk-management assets/liabilities and Note H for retirement and other postretirement benefit plan obligations. The following table sets forth information about the balance of accumulated other comprehensive loss at March 31, 2020 , representing unrealized gains (losses) related to risk-management assets and liabilities: Risk- Management Assets/Liabilities (a) ( Thousands of dollars ) Commodity derivative instruments expected to be realized within the next 21 months (b) $ 72,180 Settled interest-rate swaps to be recognized over the life of the long-term, fixed-rate debt (c) (218,877 ) Interest-rate swaps with future settlement dates expected to be amortized over the life of long-term debt (208,128 ) Accumulated other comprehensive loss at March 31, 2020 $ (354,825 ) (a) - All amounts are presented net of tax. (b) - Based on March 31, 2020 , commodity prices, we expect to realize $73.0 million in net gains, net of tax, over the next 12 months and $0.8 million in net losses, net of tax, thereafter. (c) - We expect losses of $29.4 million , net of tax, will be reclassified into earnings during the next 12 months as the hedged items affect earnings. The remaining amounts in accumulated other comprehensive loss relate primarily to our retirement and other postretirement benefit plan obligations, which are expected to be amortized over the average remaining service period of employees participating in these plans.

EARNINGS PER SHARE EARNINGS PER

EARNINGS PER SHARE EARNINGS PER SHARE (Notes)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share [Text Block]	EARNINGS PER SHARE The following tables set forth the computation of basic and diluted EPS for the periods indicated: Three Months Ended March 31, 2020 Income (Loss) Shares Per Share Amount ( Thousands, except per share amounts ) Basic EPS Net loss available for common stock $ (142,132 ) 414,282 $ (0.34 ) Diluted EPS Effect of dilutive securities — 1,066 Net loss available for common stock and common stock equivalents $ (142,132 ) 415,348 $ (0.34 ) Three Months Ended March 31, 2019 Income (Loss) Shares Per Share Amount ( Thousands, except per share amounts ) Basic EPS Net income available for common stock $ 336,933 412,908 $ 0.82 Diluted EPS Effect of dilutive securities — 2,325 Net income available for common stock and common stock equivalents $ 336,933 415,233 $ 0.81

EMPLOYEE BENEFIT PLANS EMPLOYEE

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS (Notes)	3 Months Ended
	Mar. 31, 2020
Defined Benefit Plan [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS The following table sets forth the components of net periodic benefit cost for our retirement and other postretirement benefit plans for the periods indicated: Retirement Benefits Other Postretirement Benefits Three Months Ended Three Months Ended March 31, March 31, 2020 2019 2020 2019 ( Thousands of dollars ) Components of net periodic benefit cost Service cost $ 2,036 $ 1,954 $ 115 $ 117 Interest cost 4,574 5,126 442 509 Expected return on plan assets (6,232 ) (5,892 ) (722 ) (570 ) Amortization of prior service cost (credit) (a) 28 — — (57 ) Amortization of net loss (a) 4,571 3,158 1 74 Net periodic benefit cost (income) $ 4,977 $ 4,346 $ (164 ) $ 73 (a) - These components of net periodic benefit cost are recognized in accumulated other comprehensive loss and are reclassified to other income (expense) in our Consolidated Statements of Income, with related income tax benefits of $1.1 million and $0.7 million reclassified to income tax (expense) benefit for the three months ended March 31, 2020 and 2019, respectively.

UNCONSOLIDATED AFFILIATES (Note

UNCONSOLIDATED AFFILIATES (Notes)	3 Months Ended
	Mar. 31, 2020
Equity Method Investments and Joint Ventures [Abstract]
UNCONSOLIDATED AFFILIATES	UNCONSOLIDATED AFFILIATES Equity in Net Earnings from Investments and Impairments - The following table sets forth our equity in net earnings (loss) from investments for the periods indicated: Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Northern Border Pipeline $ 22,120 $ 20,802 Overland Pass Pipeline 14,111 17,394 Roadrunner 6,433 6,338 Other 1,963 (1,053 ) Equity in net earnings from investments $ 44,627 $ 43,481 Impairment of equity investments $ (37,730 ) $ — For the three months ended March 31, 2020, we recorded a noncash impairment charge of $30.5 million related to our 10.2% investment in Venice Energy Services Company in our Natural Gas Gathering and Processing segment, which includes $22.3 million related to equity-method goodwill, and a $7.2 million noncash impairment charge related to our 50% investment in Chisholm Pipeline Company in our Natural Gas Liquids segment. Our remaining equity-method goodwill was $16.5 million at March 31, 2020. For additional information on our impairment charges, see Note A. We incurred expenses in transactions with unconsolidated affiliates of $45.3 million and $41.8 million for the three months ended March 31, 2020 and 2019 , respectively, primarily related to Overland Pass Pipeline and Northern Border Pipeline. Accounts payable to our equity-method investees at March 31, 2020 , and December 31, 2019 , were $14.7 million and $13.5 million , respectively. We have an operating agreement with Roadrunner that provides for reimbursement or payment to us for management services and certain operating costs. Reimbursements and payments from Roadrunner included in operating income (loss) in our Consolidated Statements of Income for the three months ended March 31, 2020 and 2019

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Notes)	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Environmental Matters and Pipeline Safety - The operation of pipelines, plants and other facilities for the gathering, processing, fractionation, transportation and storage of natural gas, NGLs, condensate and other products is subject to numerous and complex laws and regulations pertaining to health, safety and the environment. As an owner and/or operator of these facilities, we must comply with laws and regulations that relate to air and water quality, hazardous and solid waste management and disposal, cultural resource protection and other environmental matters. The cost of planning, designing, constructing and operating pipelines, plants and other facilities must incorporate compliance with these laws, regulations and safety standards. Failure to comply with these laws and regulations may trigger a variety of administrative, civil and potentially criminal enforcement measures, including citizen suits, which can include the assessment of monetary penalties, the imposition of remedial requirements and the issuance of injunctions or restrictions on operation or construction. Management believes that, based on currently known information, compliance with these laws and regulations will not affect adversely our consolidated results of operations, financial condition or cash flows. Legal Proceedings - We are a party to various litigation matters and claims that have arisen in the normal course of our operations. While the results of these litigation matters and claims cannot be predicted with certainty, we believe the reasonably possible losses from such matters, individually and in the aggregate, are not material. Additionally, we believe the probable final outcome of such matters will not have a material adverse effect on our consolidated results of operations, financial position or cash flows.

LEASES (Notes)

LEASES (Notes)	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Leases of Lessee Disclosure [Text Block]	LEASES In December 2019, we entered into an operating lease for pipeline capacity with a lease term of 10 years that commenced January 1, 2020. In connection with this lease, we recognized an operating lease right-of-use asset and a lease liability with remaining balances of $ 74.0 million and $ 74.2 million , respectively, as of March 31, 2020. During the three months ended March 31, 2020, we entered into certain operating leases and recognized operating lease right-of-use assets and lease liabilities with remaining balances of $17.2 million at the end of the period. At March 31, 2020, the weighted-average remaining lease term and the weighted-average discount rate for our operating leases were 8.8 years and 3.15% , respectively. The following table sets forth information about our supplemental cash flows related to our leases: Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases $ 2,840 $ 1,519 Financing cash flows for finance lease $ 469 $ 425 Right-of-use assets obtained in exchange for operating lease liabilities (noncash) $ 97,339 $ 380 The following table sets forth the maturity of our lease liabilities as of March 31, 2020 : Finance Lease Operating Leases ( Millions of dollars ) Remainder of 2020 $ 3.4 $ 12.4 2021 4.5 16.3 2022 4.5 14.9 2023 4.5 13.7 2024 4.5 12.4 2025 and beyond 17.1 57.0 Total lease payments 38.5 126.7 Less: Interest 12.7 16.8 Present value of lease liabilities $ 25.8 $ 109.9

REVENUE REVENUE (Notes)

REVENUE REVENUE (Notes)	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	REVENUES Accounting Policies - Our revenue recognition policy is described in Note A of the Notes to Consolidated Financial Statements in our Annual Report. Contract Assets and Contract Liabilities - Our contract asset balances at the beginning and end of the period primarily relate to our firm service transportation contracts with tiered rates, which are not material. The following table sets forth the balances in contract liabilities for the periods indicated: Contract Liabilities ( Millions of dollars ) Balance at December 31, 2019 (a) $ 57.1 Revenue recognized included in beginning balance (18.2 ) Net additions 6.8 Balance at March 31, 2020 (b) $ 45.7 (a) - Contract liabilities of $ 22.2 million and $ 34.9 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet. (b) - Contract liabilities of $ 11.9 million and $ 33.8 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet. Receivables from Customers and Revenue Disaggregation - Substantially all of the balances in accounts receivable on our Consolidated Balance Sheets at March 31, 2020 , and December 31, 2019 , relate to customer receivables. Revenues sources are disaggregated in Note M. Transaction Price Allocated to Unsatisfied Performance Obligations - We do not disclose the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) variable consideration on contracts for which we recognize revenue at the amount to which we have the right to invoice for services performed. The following table presents aggregate value allocated to unsatisfied performance obligations as of March 31, 2020 , and the amounts we expect to recognize in revenue in future periods, related primarily to firm transportation and storage contracts with remaining contract terms ranging from one month to 24 years : Expected Period of Recognition in Revenue ( Millions of dollars ) Remainder of 2020 $ 257.2 2021 305.3 2022 230.9 2023 184.6 2024 and beyond 853.9 Total estimated transaction price allocated to unsatisfied performance obligations $ 1,831.9 The table above excludes variable consideration allocated entirely to wholly unsatisfied performance obligations, wholly unsatisfied promises to transfer distinct goods or services that are part of a single performance obligation and consideration we determine to be fully constrained. The amounts we determined to be fully constrained relate to future sales obligations under long-term sales contracts where the transaction price is not known and minimum volume agreements, which we consider to be fully constrained until invoiced.

SEGMENTS (Notes)

SEGMENTS (Notes)	3 Months Ended
	Mar. 31, 2020
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
SEGMENTS	SEGMENTS Segment Descriptions - Our operations are divided into three reportable business segments, as follows: • our Natural Gas Gathering and Processing segment gathers, treats and processes natural gas; • our Natural Gas Liquids segment gathers, treats, fractionates and transports NGLs and stores, markets and distributes NGL products; and • our Natural Gas Pipelines segment operates regulated interstate and intrastate natural gas transmission pipelines and natural gas storage facilities. Other and eliminations consist of corporate costs, the operating and leasing activities of our headquarters building and related parking facility and eliminations necessary to reconcile our reportable segments to our Consolidated Financial Statements. Accounting Policies - The accounting policies of the segments are described in Note A of the Notes to Consolidated Financial Statements in our Annual Report. Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated: Three Months Ended Natural Gas Natural Gas Natural Gas Total Segments ( Thousands of dollars ) NGL and condensate sales $ 219,917 $ 1,596,711 $ — $ 1,816,628 Residue natural gas sales 189,051 — 2,035 191,086 Gathering, processing and exchange services revenue 37,937 120,536 — 158,473 Transportation and storage revenue — 50,755 118,364 169,119 Other 3,075 2,590 384 6,049 Total revenues (c) 449,980 1,770,592 120,783 2,341,355 Cost of sales and fuel (exclusive of depreciation and operating costs) (202,170 ) (1,278,754 ) (1,539 ) (1,482,463 ) Operating costs (84,470 ) (89,571 ) (33,307 ) (207,348 ) Equity in net earnings from investments 806 15,268 28,553 44,627 Noncash compensation expense and other (4,498 ) (6,619 ) (1,966 ) (13,083 ) Segment adjusted EBITDA $ 159,648 $ 410,916 $ 112,524 $ 683,088 Depreciation and amortization $ (58,756 ) $ (57,841 ) $ (14,769 ) $ (131,366 ) Impairment charges $ (564,353 ) $ (77,401 ) $ — $ (641,754 ) Investments in unconsolidated affiliates $ 4,276 $ 435,024 $ 371,179 $ 810,479 Total assets $ 6,374,552 $ 12,682,807 $ 2,089,362 $ 21,146,721 Capital expenditures $ 181,610 $ 746,183 $ 16,590 $ 944,383 (a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $435.1 million , of which $378.2 million related to revenues within the segment, and cost of sales and fuel of $120.4 million . (b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $73.9 million and cost of sales and fuel of $6.1 million . (c) - Intersegment revenues for the Natural Gas Gathering and Processing segment totaled $213.3 million . Intersegment revenues for the Natural Gas Liquids and Natural Gas Pipelines segments were not material. Three Months Ended Total Segments Other and Eliminations Total ( Thousands of dollars ) Reconciliations of total segments to consolidated NGL and condensate sales $ 1,816,628 $ (199,472 ) $ 1,617,156 Residue natural gas sales 191,086 (1,032 ) 190,054 Gathering, processing and exchange services revenue 158,473 — 158,473 Transportation and storage revenue 169,119 (3,809 ) 165,310 Other 6,049 (370 ) 5,679 Total revenues (a) $ 2,341,355 $ (204,683 ) $ 2,136,672 Cost of sales and fuel (exclusive of depreciation and operating costs) $ (1,482,463 ) $ 205,535 $ (1,276,928 ) Operating costs $ (207,348 ) $ 308 $ (207,040 ) Depreciation and amortization $ (131,366 ) $ (987 ) $ (132,353 ) Impairment charges $ (641,754 ) $ — $ (641,754 ) Equity in net earnings from investments $ 44,627 $ — $ 44,627 Investments in unconsolidated affiliates $ 810,479 $ — $ 810,479 Total assets $ 21,146,721 $ 822,719 $ 21,969,440 Capital expenditures $ 944,383 $ 5,296 $ 949,679 (a) - Noncustomer revenue for the three months ended March 31, 2020 , totaled $80.2 million related primarily to gains from derivatives on commodity contracts. Three Months Ended Natural Gas Gathering and Processing Natural Gas Liquids (a) Natural Gas Pipelines (b) Total Segments ( Thousands of dollars ) NGL and condensate sales $ 332,332 $ 2,158,103 $ — $ 2,490,435 Residue natural gas sales 319,036 — 970 320,006 Gathering, processing and exchange services revenue 39,742 98,534 — 138,276 Transportation and storage revenue — 52,322 112,865 165,187 Other 3,551 2,541 2,565 8,657 Total revenues (c) 694,661 2,311,500 116,400 3,122,561 Cost of sales and fuel (exclusive of depreciation and operating costs) (450,913 ) (1,846,673 ) (1,755 ) (2,299,341 ) Operating costs (94,247 ) (110,438 ) (36,268 ) (240,953 ) Equity in net earnings (loss) from investments (1,202 ) 17,544 27,139 43,481 Noncash compensation expense and other 3,945 5,706 1,132 10,783 Segment adjusted EBITDA $ 152,244 $ 377,639 $ 106,648 $ 636,531 Depreciation and amortization $ (52,681 ) $ (46,401 ) $ (14,156 ) $ (113,238 ) Investments in unconsolidated affiliates $ 39,749 $ 447,272 $ 463,903 $ 950,924 Total assets $ 6,208,883 $ 10,220,412 $ 2,138,759 $ 18,568,054 Capital expenditures $ 215,148 $ 639,338 $ 28,688 $ 883,174 (a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $323.1 million , of which $270.0 million related to sales within the segment, and cost of sales and fuel of $118.5 million . (b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $70.1 million and cost of sales and fuel of $5.6 million . (c) - Intersegment revenues for the Natural Gas Gathering and Processing segment totaled $335.8 million . Intersegment revenues for the Natural Gas Liquids and Natural Gas Pipelines segments were not material. Three Months Ended Total Segments Other and Eliminations Total ( Thousands of dollars ) Reconciliations of total segments to consolidated NGL and condensate sales $ 2,490,435 $ (338,351 ) $ 2,152,084 Residue natural gas sales 320,006 — 320,006 Gathering, processing and exchange services revenue 138,276 — 138,276 Transportation and storage revenue 165,187 (3,937 ) 161,250 Other 8,657 (315 ) 8,342 Total revenues (a) $ 3,122,561 $ (342,603 ) $ 2,779,958 Cost of sales and fuel (exclusive of depreciation and operating costs) $ (2,299,341 ) $ 342,964 $ (1,956,377 ) Operating costs $ (240,953 ) $ 212 $ (240,741 ) Depreciation and amortization $ (113,238 ) $ (920 ) $ (114,158 ) Equity in net earnings from investments $ 43,481 $ — $ 43,481 Investments in unconsolidated affiliates $ 950,924 $ — $ 950,924 Total assets $ 18,568,054 $ 366,271 $ 18,934,325 Capital expenditures $ 883,174 $ 6,531 $ 889,705 (a) - Noncustomer revenue for the three months ended March 31, 2019 , totaled $22.3 million related primarily to gains from derivatives on commodity contracts. Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Reconciliation of net income (loss) to total segment adjusted EBITDA Net income (loss) $ (141,857 ) $ 337,208 Add: Interest expense, net of capitalized interest 140,616 115,420 Depreciation and amortization 132,353 114,158 Income tax expense (benefit) (55,395 ) 77,934 Impairment charges 641,754 — Noncash compensation expense (1,302 ) 5,540 Other corporate costs and noncash items (a) (33,081 ) (13,729 ) Total segment adjusted EBITDA $ 683,088 $ 636,531 (a) - The three months ended March 31, 2020, includes a corporate $15.8 million gain on extinguishment of debt related to open market repurchases.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairment or Disposal of Long-Lived Assets, Including Intangible Assets, Policy [Policy Text Block]	Impairment Charges - Late in the first quarter 2020, we experienced a significant decline in our share price and market capitalization as the energy industry experienced historic events that led to a simultaneous demand and supply shock. The World Health Organization declared the novel strain of COVID-19 a global pandemic and recommended containment and mitigation measures worldwide, which contributed to a massive economic slowdown and decreased demand for crude oil. In addition, Saudi Arabia and Russia increased production of crude oil as the two countries competed for market share. As a result, the global supply of crude oil significantly exceeded demand and led to a collapse in crude oil prices. Despite recently announced production cuts from many oil producing countries, supply exceeds demand, crude oil storage is near capacity and prices remain volatile. The collapse in crude oil prices and demand for energy commodities have also contributed to lower NGL product prices and lower natural gas prices, which is creating challenges for crude oil and natural gas producers as they assess their future drilling and production plans. Based on these events, we performed a Step 1 analysis to test our goodwill for impairment and evaluated certain long-lived asset groups and equity investments for impairment. Goodwill - We assess our goodwill for impairment at least annually on July 1, unless events or changes in circumstances indicate an impairment may have occurred before that time. In the Step 1 analysis, an assessment is made by comparing the fair value of a reporting unit with its carrying amount, including goodwill. If the carrying value of a reporting unit exceeds its fair value, an impairment loss is recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit. In January 2020, we adopted ASU 2017-04, in which the requirement to calculate the implied fair value of goodwill under the two-step impairment test was eliminated. To estimate the fair value of our reporting units, we use two generally accepted valuation approaches, an income approach and a market approach, using assumptions consistent with a market participant’s perspective. Under the income approach, we use anticipated cash flows over a period of years plus a terminal value and discount these amounts to their present value using appropriate discount rates. Under the market approach, we apply EBITDA multiples to forecasted EBITDA. The multiples used are consistent with historical asset transactions. The forecasted cash flows are based on average forecasted cash flows for a reporting unit over a period of years. Based on the results of our impairment test, we concluded the carrying value of the Natural Gas Gathering and Processing reporting unit exceeded its estimated fair value, resulting in a noncash impairment charge of $153.4 million for the three months ended March 31, 2020, which is included within impairment charges in our Consolidated Statement of Income. The estimated fair value of our Natural Gas Liquids and Natural Gas Pipelines reporting units substantially exceeded their respective carrying values. The following table sets forth our goodwill, by segment, for the periods indicated: March 31, December 31, ( Thousands of dollars ) Natural Gas Gathering and Processing $ — $ 153,404 Natural Gas Liquids 371,217 371,217 Natural Gas Pipelines 156,375 156,375 Total goodwill $ 527,592 $ 680,996 Long-lived assets - We assess our long-lived assets for impairment whenever events or changes in circumstances indicate that an asset’s carrying amount may not be recoverable. An impairment is indicated if the carrying amount of a long-lived asset exceeds the sum of the undiscounted future cash flows expected to result from the use and eventual disposition of the asset. If an impairment is indicated, we record an impairment loss equal to the difference between the carrying value and the fair value of the long-lived asset. We evaluated our Natural Gas Gathering and Processing segment asset groups and determined that the carrying value of certain long-lived asset groups in western Oklahoma, Kansas and the Powder River Basin, where lower pricing is expected to impact drilling and production levels, are not recoverable and exceeded their estimated fair value. We recorded noncash impairment charges of $380.5 million for the three months ended March 31, 2020, which includes impairment to intangible assets of $19.9 million related to supply contracts. In our Natural Gas Liquids segment, we recorded noncash impairment charges of $70.2 million for the three months ended March 31, 2020, related to certain inactive assets, as our expectation for future use of the assets changed. These charges are included within impairment charges in our Consolidated Statement of Income. Investments in unconsolidated affiliates - The impairment test for equity-method investments considers whether the fair value of the equity investment as a whole, not the underlying net assets, has declined and whether that decline is other than temporary. Therefore, we periodically evaluate the amount at which we carry our equity-method investments to determine whether current events or circumstances warrant adjustments to our carrying values. We evaluated our investments in unconsolidated affiliates and concluded that the carrying value of our 10.2% investment in Venice Energy Services Company in our Natural Gas Gathering and Processing segment exceeded its estimated fair value, resulting in a noncash impairment charge of $30.5 million for the three months ended March 31, 2020, which includes an impairment to our equity-method goodwill of $22.3 million . We also concluded that the carrying value of our 50% investment in Chisholm Pipeline Company in our Natural Gas Liquids segment exceeded its estimated fair value, resulting in a noncash impairment charge of $7.2 million for the three months ended March 31, 2020. These impairment charges are included within impairment of equity investments in our Consolidated Statement of Income.
Basis of Accounting, Policy [Policy Text Block]	Our accompanying unaudited Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the SEC. These statements have been prepared in accordance with GAAP and reflect all adjustments that, in our opinion, are necessary for a fair statement of the results for the interim periods presented. All such adjustments are of a normal recurring nature. The 2019 year-end Consolidated Balance Sheet data was derived from our audited Consolidated Financial Statements but does not include all disclosures required by GAAP. Certain reclassifications have been made in the prior-year Consolidated Financial Statements to conform to the current year presentation. These unaudited Consolidated Financial Statements should be read in conjunction with our audited Consolidated Financial Statements in our Annual Report.
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Issued Accounting Standards Update - Changes to GAAP are established by the Financial Accounting Standards Board (FASB) in the form of ASUs to the FASB Accounting Standards Codification. We consider the applicability and impact of all ASUs. ASUs not listed below or in our Annual Report were assessed and determined to be either not applicable or clarifications of ASUs previously issued or listed below. Except as discussed below or in our Annual Report, there have been no new accounting pronouncements that have become effective or have been issued that are of significance or potential significance to us. The following table provides a brief description of recently adopted accounting pronouncements and our analysis of the effects on our financial statements: Standard Description Date of Adoption Effect on the Financial Statements or Other Significant Matters ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” The standard requires a financial asset (or a group of financial assets) measured at amortized cost basis to be presented net of the allowance for credit losses to reflect the net carrying value at the amount expected to be collected on the financial asset; and the initial allowance for credit losses for purchased financial assets, including available-for-sale debt securities, to be added to the purchase price rather than being reported as a credit loss expense. First quarter 2020 The impact of adopting this standard was not material. ASU 2017-04, “Intangibles- Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” The standard simplifies the subsequent measurement of goodwill by eliminating the requirement to calculate the implied fair value of goodwill under step 2. Instead, an entity will recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. The standard does not change step zero or step 1 assessments. First quarter 2020 We adopted and implemented this standard to record noncash impairment charges related to our goodwill, as described above. ASU 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting” The standard provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. First quarter 2020 The impact of adopting this standard was not material.

FAIR VALUE MEASUREMENTS FAIR VA

FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS (Policies)	3 Months Ended
	Mar. 31, 2020
Fair Value Accounting Policy [Abstract]
Fair Value of Financial Instruments, Policy [Policy Text Block]	Determining Fair Value - For our fair value measurements, we utilize market prices, third-party pricing services, present value methods and standard option valuation models to determine the price we would receive from the sale of an asset or the transfer of a liability in an orderly transaction at the measurement date. We measure the fair value of a group of financial assets and liabilities consistent with how a market participant would price the net risk exposure at the measurement date. Many of the contracts in our derivative portfolio are executed in liquid markets where price transparency exists. Our financial commodity derivatives are generally settled through a NYMEX or Intercontinental Exchange (ICE) clearing broker account with daily margin requirements. We validate our valuation inputs with third-party information and settlement prices from other sources, where available. We compute the fair value of our derivative portfolio by discounting the projected future cash flows from our derivative assets and liabilities to present value using interest-rate yields to calculate present-value discount factors derived from the implied forward LIBOR yield curve. The fair value of our forward-starting interest-rate swaps is determined using financial models that incorporate the implied forward LIBOR yield curve for the same period as the future interest-rate swap settlements. We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using counterparty-specific bond yields. Although we use our best estimates to determine the fair value of the derivative contracts we have executed, the ultimate market prices realized could differ materially from our estimates. Fair Value Hierarchy - At each balance sheet date, we utilize a fair value hierarchy to classify fair value amounts recognized or disclosed in our financial statements based on the observability of inputs used to estimate such fair value. The levels of the hierarchy are described below: • Level 1 - fair value measurements are based on unadjusted quoted prices for identical securities in active markets. These balances are composed predominantly of exchange-traded derivative contracts for natural gas and crude oil. • Level 2 - fair value measurements are based on significant observable pricing inputs, including quoted prices for similar assets and liabilities in active markets and inputs from third-party pricing services supported with corroborative evidence. These balances are composed of over-the-counter interest-rate derivatives. • Level 3 - fair value measurements are based on inputs that may include one or more unobservable inputs, including internally developed commodity price curves that incorporate market data from broker quotes and third-party pricing services. These balances are composed predominantly of exchange-cleared and over-the-counter derivatives to hedge NGL price risk and natural gas basis risk between various transaction locations and the NYMEX Henry Hub. Our commodity derivatives are generally valued using forward quotes provided by third-party pricing services that are validated with other market data. We believe any measurement uncertainty at March 31, 2020, is immaterial as our Level 3 fair value measurements are based on unadjusted pricing information from broker quotes and third-party pricing services. We do not believe that our Level 3 fair value estimates have a material impact on our results of operations, as our derivatives are accounted for as hedges. Determining the appropriate classification of our fair value measurements within the fair value hierarchy requires management’s judgment regarding the degree to which market data is observable or corroborated by observable market data. We categorize derivatives for which fair value is determined using multiple inputs within a single level, based on the lowest level input that is significant to the fair value measurement in its entirety.

REVENUE REVENUE (Policies)

REVENUE REVENUE (Policies)	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Policy Text Block]	Accounting Policies

SEGMENTS SEGMENTS (Policies)

SEGMENTS SEGMENTS (Policies)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Segment Accounting Policy [Policy Text Block]	Accounting Policies - The accounting policies of the segments are described in Note A of the Notes to Consolidated Financial Statements in our Annual Report.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill by Segment	The following table sets forth our goodwill, by segment, for the periods indicated: March 31, December 31, ( Thousands of dollars ) Natural Gas Gathering and Processing $ — $ 153,404 Natural Gas Liquids 371,217 371,217 Natural Gas Pipelines 156,375 156,375 Total goodwill $ 527,592 $ 680,996

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Recurring Fair Value Measurements	The following tables set forth our recurring fair value measurements for the periods indicated: March 31, 2020 Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net ( Thousands of dollars ) Derivative assets Commodity contracts Financial contracts $ 37,599 $ — $ 130,272 $ 167,871 $ (140,707 ) $ 27,164 Total derivative assets $ 37,599 $ — $ 130,272 $ 167,871 $ (140,707 ) $ 27,164 Derivative liabilities Commodity contracts Financial contracts $ (911 ) $ — $ (72,871 ) $ (73,783 ) $ 73,783 $ — Interest-rate contracts — (270,297 ) — (270,297 ) — (270,297 ) Total derivative liabilities $ (911 ) $ (270,297 ) $ (72,871 ) $ (344,080 ) $ 73,783 $ (270,297 ) (a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheet on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At March 31, 2020 , we posted no cash and held cash of $66.9 million from various counterparties, which offsets our derivative net asset position under master netting arrangements as shown in the table above. December 31, 2019 Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net ( Thousands of dollars ) Derivative assets Commodity contracts Financial contracts $ 10,892 $ — $ 55,557 $ 66,449 $ (28,588 ) $ 37,861 Interest-rate contracts — 581 — 581 — 581 Total derivative assets $ 10,892 $ 581 $ 55,557 $ 67,030 $ (28,588 ) $ 38,442 Derivative liabilities Commodity contracts Financial contracts $ (4,811 ) $ — $ (24,785 ) $ (29,596 ) $ 28,588 $ (1,008 ) Interest-rate contracts — (201,941 ) — (201,941 ) — (201,941 ) Total derivative liabilities $ (4,811 ) $ (201,941 ) $ (24,785 ) $ (231,537 ) $ 28,588 $ (202,949 ) (a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheet on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2019 , we held no cash and posted $8.8 million of cash with various counterparties, which is included in other current assets in our Consolidated Balance Sheet.
Reconciliation of Level 3 Fair Value Measurements	The following table sets forth a reconciliation of our Level 3 fair value measurements for the periods indicated: Three Months Ended March 31, Derivative Assets (Liabilities) 2020 2019 ( Thousands of dollars ) Net assets at beginning of period $ 30,772 $ 40,484 Total changes in fair value: Settlements included in net income (loss) (a) (16,146 ) (25,361 ) New Level 3 derivatives included in other comprehensive income (loss) (b) 20,993 1,597 Unrealized change included in other comprehensive income (loss) (b) 21,782 (5,191 ) Net assets at end of period $ 57,401 $ 11,529 (a) - Included in commodity sales revenues/cost of sales and fuel in our Consolidated Statements of Income.

RISK MANAGEMENT AND HEDGING A_2

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES (Tables)	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivatives	The following table sets forth the fair values of our derivative instruments presented on a gross basis for the periods indicated: March 31, 2020 December 31, 2019 Location in our Consolidated Balance Sheets Assets (Liabilities) Assets (Liabilities) ( Thousands of dollars ) Commodity contracts (a) Financial contracts Other current assets $ 167,871 $ (73,783 ) $ 64,858 $ (26,997 ) Other deferred credits — — 1,591 (2,599 ) Interest-rate contracts Other current liabilities — (28,673 ) — (90,161 ) Other assets/other deferred credits — (241,624 ) 581 (111,780 ) Total derivative instruments $ 167,871 $ (344,080 ) $ 67,030 $ (231,537 ) (a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us.
Notional Amounts of Derivative Instruments	The following table sets forth the notional quantities for derivative instruments held for the periods indicated: March 31, 2020 December 31, 2019 Contract Type Purchased/ Payor Sold/ Receiver Purchased/ Payor Sold/ Receiver Cash flow hedges Fixed price - Natural gas ( Bcf ) Futures and swaps — (47.6 ) — (59.0 ) - Crude oil and NGLs ( MMBbl ) Futures, forwards and swaps 10.5 (17.5 ) 7.9 (17.4 ) Basis - Natural gas ( Bcf ) Futures and swaps — (47.6 ) — (59.0 ) Interest-rate contracts ( Billions of dollars ) Swaps $ 2.4 $ — $ 3.1 $ —
Schedule of Cash Flow Hedging Instruments Effect on Comprehensive Income (Loss)	The following table sets forth the unrealized change in fair value of cash flow hedges in other comprehensive income (loss) for the periods indicated: Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Commodity contracts $ 87,195 $ (21,625 ) Interest-rate contracts (225,041 ) (67,912 ) Total unrealized change in fair value of cash flow hedges in other comprehensive income (loss) $ (137,846 ) $ (89,537 )
Schedule of Cash Flow Hedging Instruments Effect on Income (Loss)	The following table sets forth the effect of cash flow hedges on net income (loss) for the periods indicated: Location of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income (Loss) Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Commodity contracts Commodity sales revenues $ 44,999 $ 23,822 Cost of sales and fuel (15,039 ) (4,970 ) Interest-rate contracts Interest expense (10,278 ) (2,504 ) Total change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income (loss) on derivatives $ 19,682 $ 16,348

DEBT DEBT (Tables)

DEBT DEBT (Tables)	3 Months Ended
	Mar. 31, 2020
Debt Instrument [Line Items]
Debt [Table Text Block]	The following table sets forth our consolidated debt for the periods indicated: March 31, December 31, ( Thousands of dollars ) Commercial paper outstanding, bearing a weighted-average interest rate of 2.16% as of December 31, 2019 $ — $ 220,000 Senior unsecured obligations: $1,500,000 term loan, variable rate, due November 2021 1,250,000 1,250,000 $700,000 at 4.25% due February 2022 547,397 547,397 $900,000 at 3.375% due October 2022 900,000 900,000 $425,000 at 5.0% due September 2023 425,000 425,000 $500,000 at 7.5% due September 2023 500,000 500,000 $500,000 at 2.75% due September 2024 500,000 500,000 $500,000 at 4.9% due March 2025 500,000 500,000 $400,000 at 2.2% due September 2025 397,000 — $500,000 at 4.0% due July 2027 500,000 500,000 $800,000 at 4.55% due July 2028 800,000 800,000 $100,000 at 6.875% due September 2028 100,000 100,000 $700,000 at 4.35% due March 2029 700,000 700,000 $750,000 at 3.4% due September 2029 734,251 750,000 $850,000 at 3.1% due March 2030 821,050 — $400,000 at 6.0% due June 2035 400,000 400,000 $600,000 at 6.65% due October 2036 600,000 600,000 $600,000 at 6.85% due October 2037 600,000 600,000 $650,000 at 6.125% due February 2041 650,000 650,000 $400,000 at 6.2% due September 2043 400,000 400,000 $700,000 at 4.95% due July 2047 693,405 700,000 $1,000,000 at 5.2% due July 2048 1,000,000 1,000,000 $750,000 at 4.45% due September 2049 747,650 750,000 $500,000 at 4.5% due March 2050 489,625 — Guardian Pipeline Weighted average 7.85% due December 2022 19,395 21,307 Total debt 14,274,773 12,813,704 Unamortized portion of terminated swaps 14,603 15,032 Unamortized debt issuance costs and discounts (135,076 ) (121,329 ) Current maturities of long-term debt (7,650 ) (7,650 ) Short-term borrowings (a) — (220,000 ) Long-term debt $ 14,146,650 $ 12,479,757 (a) - Individual issuances of commercial paper under our commercial paper program generally mature in 90 days or less.

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	3 Months Ended
	Mar. 31, 2020
Accumulated Other Comprehensive Loss	The following table sets forth the balance in accumulated other comprehensive loss for the period indicated: Risk- Management Assets/Liabilities (a) Retirement and Other Postretirement Benefit Plan Obligations (a) (b) Risk- Management Assets/Liabilities of Unconsolidated Affiliates (a) Accumulated Other Comprehensive Loss (a) ( Thousands of dollars ) January 1, 2020 $ (233,520 ) $ (131,481 ) $ (8,999 ) $ (374,000 ) Other comprehensive income (loss) before reclassifications (106,141 ) 20 (7,777 ) (113,898 ) Amounts reclassified to net income (loss) (c) (15,164 ) 3,542 134 (11,488 ) Other comprehensive income (loss) (121,305 ) 3,562 (7,643 ) (125,386 ) March 31, 2020 $ (354,825 ) $ (127,919 ) $ (16,642 ) $ (499,386 ) (a) - All amounts are presented net of tax. (b) - Includes amounts related to supplemental executive retirement plan. (c) - See Note C for details of amounts reclassified to net income (loss) for risk-management assets/liabilities and Note H for retirement and other postretirement benefit plan obligations.
Schedule of Accumulated Other Comprehensive Loss for Risk-Management Assets/Liabilities [Table Text Block]	The following table sets forth information about the balance of accumulated other comprehensive loss at March 31, 2020 , representing unrealized gains (losses) related to risk-management assets and liabilities: Risk- Management Assets/Liabilities (a) ( Thousands of dollars ) Commodity derivative instruments expected to be realized within the next 21 months (b) $ 72,180 Settled interest-rate swaps to be recognized over the life of the long-term, fixed-rate debt (c) (218,877 ) Interest-rate swaps with future settlement dates expected to be amortized over the life of long-term debt (208,128 ) Accumulated other comprehensive loss at March 31, 2020 $ (354,825 ) (a) - All amounts are presented net of tax. (b) - Based on March 31, 2020 , commodity prices, we expect to realize $73.0 million in net gains, net of tax, over the next 12 months and $0.8 million in net losses, net of tax, thereafter. (c) - We expect losses of $29.4 million , net of tax, will be reclassified into earnings during the next 12 months as the hedged items affect earnings.

EARNINGS PER SHARE EARNINGS P_2

EARNINGS PER SHARE EARNINGS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share	The following tables set forth the computation of basic and diluted EPS for the periods indicated: Three Months Ended March 31, 2020 Income (Loss) Shares Per Share Amount ( Thousands, except per share amounts ) Basic EPS Net loss available for common stock $ (142,132 ) 414,282 $ (0.34 ) Diluted EPS Effect of dilutive securities — 1,066 Net loss available for common stock and common stock equivalents $ (142,132 ) 415,348 $ (0.34 ) Three Months Ended March 31, 2019 Income (Loss) Shares Per Share Amount ( Thousands, except per share amounts ) Basic EPS Net income available for common stock $ 336,933 412,908 $ 0.82 Diluted EPS Effect of dilutive securities — 2,325 Net income available for common stock and common stock equivalents $ 336,933 415,233 $ 0.81

EMPLOYEE BENEFIT PLANS EMPLOY_2

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS (Tables)	3 Months Ended
	Mar. 31, 2020
Defined Benefit Plan [Abstract]
Components of net periodic benefit cost for retirement and other postretirement benefit plans	The following table sets forth the components of net periodic benefit cost for our retirement and other postretirement benefit plans for the periods indicated: Retirement Benefits Other Postretirement Benefits Three Months Ended Three Months Ended March 31, March 31, 2020 2019 2020 2019 ( Thousands of dollars ) Components of net periodic benefit cost Service cost $ 2,036 $ 1,954 $ 115 $ 117 Interest cost 4,574 5,126 442 509 Expected return on plan assets (6,232 ) (5,892 ) (722 ) (570 ) Amortization of prior service cost (credit) (a) 28 — — (57 ) Amortization of net loss (a) 4,571 3,158 1 74 Net periodic benefit cost (income) $ 4,977 $ 4,346 $ (164 ) $ 73 (a) - These components of net periodic benefit cost are recognized in accumulated other comprehensive loss and are reclassified to other income (expense) in our Consolidated Statements of Income, with related income tax benefits of $1.1 million and $0.7 million reclassified to income tax (expense) benefit for the three months ended March 31, 2020 and 2019, respectively.

UNCONSOLIDATED AFFILIATES (Tabl

UNCONSOLIDATED AFFILIATES (Tables)	3 Months Ended
	Mar. 31, 2020
Equity In Net Earnings From Investments
Schedule of Equity Method Investments [Line Items]
Schedule of Equity Method Investments [Table Text Block]	The following table sets forth our equity in net earnings (loss) from investments for the periods indicated: Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Northern Border Pipeline $ 22,120 $ 20,802 Overland Pass Pipeline 14,111 17,394 Roadrunner 6,433 6,338 Other 1,963 (1,053 ) Equity in net earnings from investments $ 44,627 $ 43,481 Impairment of equity investments $ (37,730 ) $ —

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Lease Assets and Liabilities Included in the Consolidated Balance Sheet[Table Text Block]	The following table sets forth information about our supplemental cash flows related to our leases: Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases $ 2,840 $ 1,519 Financing cash flows for finance lease $ 469 $ 425 Right-of-use assets obtained in exchange for operating lease liabilities (noncash) $ 97,339 $ 380
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	The following table sets forth the maturity of our lease liabilities as of March 31, 2020 : Finance Lease Operating Leases ( Millions of dollars ) Remainder of 2020 $ 3.4 $ 12.4 2021 4.5 16.3 2022 4.5 14.9 2023 4.5 13.7 2024 4.5 12.4 2025 and beyond 17.1 57.0 Total lease payments 38.5 126.7 Less: Interest 12.7 16.8 Present value of lease liabilities $ 25.8 $ 109.9
Finance Lease, Liability, Maturity [Table Text Block]	The following table sets forth the maturity of our lease liabilities as of March 31, 2020 : Finance Lease Operating Leases ( Millions of dollars ) Remainder of 2020 $ 3.4 $ 12.4 2021 4.5 16.3 2022 4.5 14.9 2023 4.5 13.7 2024 4.5 12.4 2025 and beyond 17.1 57.0 Total lease payments 38.5 126.7 Less: Interest 12.7 16.8 Present value of lease liabilities $ 25.8 $ 109.9

REVENUE REVENUE (Tables)

REVENUE REVENUE (Tables)	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset and Liability [Table Text Block]	The following table sets forth the balances in contract liabilities for the periods indicated: Contract Liabilities ( Millions of dollars ) Balance at December 31, 2019 (a) $ 57.1 Revenue recognized included in beginning balance (18.2 ) Net additions 6.8 Balance at March 31, 2020 (b) $ 45.7 (a) - Contract liabilities of $ 22.2 million and $ 34.9 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet. (b) - Contract liabilities of $ 11.9 million and $ 33.8 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	The following table presents aggregate value allocated to unsatisfied performance obligations as of March 31, 2020 , and the amounts we expect to recognize in revenue in future periods, related primarily to firm transportation and storage contracts with remaining contract terms ranging from one month to 24 years : Expected Period of Recognition in Revenue ( Millions of dollars ) Remainder of 2020 $ 257.2 2021 305.3 2022 230.9 2023 184.6 2024 and beyond 853.9 Total estimated transaction price allocated to unsatisfied performance obligations $ 1,831.9

SEGMENTS (Tables)

SEGMENTS (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Segments	Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated: Three Months Ended Natural Gas Natural Gas Natural Gas Total Segments ( Thousands of dollars ) NGL and condensate sales $ 219,917 $ 1,596,711 $ — $ 1,816,628 Residue natural gas sales 189,051 — 2,035 191,086 Gathering, processing and exchange services revenue 37,937 120,536 — 158,473 Transportation and storage revenue — 50,755 118,364 169,119 Other 3,075 2,590 384 6,049 Total revenues (c) 449,980 1,770,592 120,783 2,341,355 Cost of sales and fuel (exclusive of depreciation and operating costs) (202,170 ) (1,278,754 ) (1,539 ) (1,482,463 ) Operating costs (84,470 ) (89,571 ) (33,307 ) (207,348 ) Equity in net earnings from investments 806 15,268 28,553 44,627 Noncash compensation expense and other (4,498 ) (6,619 ) (1,966 ) (13,083 ) Segment adjusted EBITDA $ 159,648 $ 410,916 $ 112,524 $ 683,088 Depreciation and amortization $ (58,756 ) $ (57,841 ) $ (14,769 ) $ (131,366 ) Impairment charges $ (564,353 ) $ (77,401 ) $ — $ (641,754 ) Investments in unconsolidated affiliates $ 4,276 $ 435,024 $ 371,179 $ 810,479 Total assets $ 6,374,552 $ 12,682,807 $ 2,089,362 $ 21,146,721 Capital expenditures $ 181,610 $ 746,183 $ 16,590 $ 944,383 (a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $435.1 million , of which $378.2 million related to revenues within the segment, and cost of sales and fuel of $120.4 million . (b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $73.9 million and cost of sales and fuel of $6.1 million . (c) - Intersegment revenues for the Natural Gas Gathering and Processing segment totaled $213.3 million . Intersegment revenues for the Natural Gas Liquids and Natural Gas Pipelines segments were not material. Three Months Ended Total Segments Other and Eliminations Total ( Thousands of dollars ) Reconciliations of total segments to consolidated NGL and condensate sales $ 1,816,628 $ (199,472 ) $ 1,617,156 Residue natural gas sales 191,086 (1,032 ) 190,054 Gathering, processing and exchange services revenue 158,473 — 158,473 Transportation and storage revenue 169,119 (3,809 ) 165,310 Other 6,049 (370 ) 5,679 Total revenues (a) $ 2,341,355 $ (204,683 ) $ 2,136,672 Cost of sales and fuel (exclusive of depreciation and operating costs) $ (1,482,463 ) $ 205,535 $ (1,276,928 ) Operating costs $ (207,348 ) $ 308 $ (207,040 ) Depreciation and amortization $ (131,366 ) $ (987 ) $ (132,353 ) Impairment charges $ (641,754 ) $ — $ (641,754 ) Equity in net earnings from investments $ 44,627 $ — $ 44,627 Investments in unconsolidated affiliates $ 810,479 $ — $ 810,479 Total assets $ 21,146,721 $ 822,719 $ 21,969,440 Capital expenditures $ 944,383 $ 5,296 $ 949,679 (a) - Noncustomer revenue for the three months ended March 31, 2020 , totaled $80.2 million related primarily to gains from derivatives on commodity contracts. Three Months Ended Natural Gas Gathering and Processing Natural Gas Liquids (a) Natural Gas Pipelines (b) Total Segments ( Thousands of dollars ) NGL and condensate sales $ 332,332 $ 2,158,103 $ — $ 2,490,435 Residue natural gas sales 319,036 — 970 320,006 Gathering, processing and exchange services revenue 39,742 98,534 — 138,276 Transportation and storage revenue — 52,322 112,865 165,187 Other 3,551 2,541 2,565 8,657 Total revenues (c) 694,661 2,311,500 116,400 3,122,561 Cost of sales and fuel (exclusive of depreciation and operating costs) (450,913 ) (1,846,673 ) (1,755 ) (2,299,341 ) Operating costs (94,247 ) (110,438 ) (36,268 ) (240,953 ) Equity in net earnings (loss) from investments (1,202 ) 17,544 27,139 43,481 Noncash compensation expense and other 3,945 5,706 1,132 10,783 Segment adjusted EBITDA $ 152,244 $ 377,639 $ 106,648 $ 636,531 Depreciation and amortization $ (52,681 ) $ (46,401 ) $ (14,156 ) $ (113,238 ) Investments in unconsolidated affiliates $ 39,749 $ 447,272 $ 463,903 $ 950,924 Total assets $ 6,208,883 $ 10,220,412 $ 2,138,759 $ 18,568,054 Capital expenditures $ 215,148 $ 639,338 $ 28,688 $ 883,174 (a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $323.1 million , of which $270.0 million related to sales within the segment, and cost of sales and fuel of $118.5 million . (b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $70.1 million and cost of sales and fuel of $5.6 million . (c) - Intersegment revenues for the Natural Gas Gathering and Processing segment totaled $335.8 million . Intersegment revenues for the Natural Gas Liquids and Natural Gas Pipelines segments were not material. Three Months Ended Total Segments Other and Eliminations Total ( Thousands of dollars ) Reconciliations of total segments to consolidated NGL and condensate sales $ 2,490,435 $ (338,351 ) $ 2,152,084 Residue natural gas sales 320,006 — 320,006 Gathering, processing and exchange services revenue 138,276 — 138,276 Transportation and storage revenue 165,187 (3,937 ) 161,250 Other 8,657 (315 ) 8,342 Total revenues (a) $ 3,122,561 $ (342,603 ) $ 2,779,958 Cost of sales and fuel (exclusive of depreciation and operating costs) $ (2,299,341 ) $ 342,964 $ (1,956,377 ) Operating costs $ (240,953 ) $ 212 $ (240,741 ) Depreciation and amortization $ (113,238 ) $ (920 ) $ (114,158 ) Equity in net earnings from investments $ 43,481 $ — $ 43,481 Investments in unconsolidated affiliates $ 950,924 $ — $ 950,924 Total assets $ 18,568,054 $ 366,271 $ 18,934,325 Capital expenditures $ 883,174 $ 6,531 $ 889,705 (a) - Noncustomer revenue for the three months ended March 31, 2019 , totaled $22.3 million related primarily to gains from derivatives on commodity contracts. Three Months Ended March 31, 2020 2019 ( Thousands of dollars ) Reconciliation of net income (loss) to total segment adjusted EBITDA Net income (loss) $ (141,857 ) $ 337,208 Add: Interest expense, net of capitalized interest 140,616 115,420 Depreciation and amortization 132,353 114,158 Income tax expense (benefit) (55,395 ) 77,934 Impairment charges 641,754 — Noncash compensation expense (1,302 ) 5,540 Other corporate costs and noncash items (a) (33,081 ) (13,729 ) Total segment adjusted EBITDA $ 683,088 $ 636,531 (a) - The three months ended March 31, 2020, includes a corporate $15.8 million gain on extinguishment of debt related to open market repurchases.

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Entity Information [Line Items]
Goodwill	$ 527,592		$ 680,996
Impairment of equity investments	37,730	$ 0
Natural Gas Gathering And Processing [Member]
Entity Information [Line Items]
Impairment of long-lived assets	380,500
Impairment of intangible assets	19,900
Goodwill	0		153,404
Goodwill impairment charge	$ 153,400
Natural Gas Gathering And Processing [Member] | Venice Energy Services Company [Member]
Entity Information [Line Items]
Equity Method Investment, Ownership Percentage	10.20%
Impairment of equity investments - goodwill	$ 22,300
Impairment of equity investments	30,500
Natural Gas Liquids
Entity Information [Line Items]
Impairment of long-lived assets	70,200
Goodwill	$ 371,217		371,217
Natural Gas Liquids | Chisholm Pipeline Company [Member]
Entity Information [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Impairment of equity investments	$ 7,200
Natural Gas Pipelines
Entity Information [Line Items]
Goodwill	$ 156,375		$ 156,375

FAIR VALUE MEASUREMENTS - Part

FAIR VALUE MEASUREMENTS - Part 1 (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash held - offsetting derivative net asset positions under master-netting arrangements	$ (66,900)	$ 0
Cash posted - total	0	8,800
Long-term debt, Fair Value	11,900,000	13,800,000
Long-term debt	14,200,000	12,500,000
Fair Value, Recurring [Member]
Derivative assets
Derivative assets	27,164	38,442
Derivative assets netting	(140,707)	(28,588)
Derivative liabilities
Derivative liabilities	(270,297)	(202,949)
Derivative liabilities netting	73,783	28,588
Fair Value, Recurring [Member] | Financial Contracts [Member]
Derivative assets
Derivative assets	27,164	37,861
Derivative assets netting	(140,707)	(28,588)
Derivative liabilities
Derivative liabilities	0	(1,008)
Derivative liabilities netting	73,783	28,588
Fair Value, Recurring [Member] | Interest-rate contracts
Derivative assets
Interest-rate contracts		581
Derivative assets netting		0
Derivative liabilities
Interest rate derivative liabilities, at fair value	(270,297)	(201,941)
Derivative liabilities netting	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Derivative assets
Derivative asset, fair value, gross	37,599	10,892
Derivative liability, fair value, gross	(911)	(4,811)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Financial Contracts [Member]
Derivative assets
Derivative asset, fair value, gross	37,599	10,892
Derivative liability, fair value, gross	(911)	(4,811)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest-rate contracts
Derivative assets
Interest-rate contracts		0
Derivative liabilities
Interest rate derivative liabilities, at fair value	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Derivative assets
Derivative asset, fair value, gross	0	581
Derivative liability, fair value, gross	(270,297)	(201,941)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Financial Contracts [Member]
Derivative assets
Derivative asset, fair value, gross	0	0
Derivative liability, fair value, gross	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest-rate contracts
Derivative assets
Interest-rate contracts		581
Derivative liabilities
Interest rate derivative liabilities, at fair value	(270,297)	(201,941)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Derivative assets
Derivative asset, fair value, gross	130,272	55,557
Derivative liability, fair value, gross	(72,871)	(24,785)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Financial Contracts [Member]
Derivative assets
Derivative asset, fair value, gross	130,272	55,557
Derivative liability, fair value, gross	(72,871)	(24,785)
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest-rate contracts
Derivative assets
Interest-rate contracts		0
Derivative liabilities
Interest rate derivative liabilities, at fair value	0	0
Fair Value, Recurring [Member] | Estimate of Fair Value Measurement [Member]
Derivative assets
Derivative asset, fair value, gross	167,871	67,030
Derivative liability, fair value, gross	(344,080)	(231,537)
Fair Value, Recurring [Member] | Estimate of Fair Value Measurement [Member] | Financial Contracts [Member]
Derivative assets
Derivative asset, fair value, gross	167,871	66,449
Derivative liability, fair value, gross	(73,783)	(29,596)
Fair Value, Recurring [Member] | Estimate of Fair Value Measurement [Member] | Interest-rate contracts
Derivative assets
Interest-rate contracts		581
Derivative liabilities
Interest rate derivative liabilities, at fair value	$ (270,297)	$ (201,941)

FAIR VALUE MEASUREMENTS - Par_2

FAIR VALUE MEASUREMENTS - Part 2 (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Fair Value, Assets And Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Net assets (liabilities) at beginning of period	$ 30,772	$ 40,484
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	(16,146)	(25,361)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, New Level 3 Derivatives	20,993	1,597
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Unrealized Change Included in other comprehensive income (loss)	21,782	(5,191)
Net assets (liabilities) at end of period	57,401	11,529
Transfers in or out of level 3	$ 0	$ 0

RISK MANAGEMENT AND HEDGING A_3

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES Part 1 (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivative, Fair Value [Line Items]
Derivative, Net Liability Position, Aggregate Fair Value	$ 0
Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	167,871	$ 67,030
(Liabilities)	(344,080)	(231,537)
Natural Gas Pipelines
Derivative, Fair Value [Line Items]
Derivative, Fair Value, Net	0	0
Other Current Assets [Member] | Commodity contracts | Financial contracts | Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	167,871	64,858
(Liabilities)	(73,783)	(26,997)
Other Current Liabilities [Member] | Interest-rate contracts | Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	0	0
(Liabilities)	(28,673)	(90,161)
Other Deferred Credits | Commodity contracts | Financial contracts | Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	0	1,591
(Liabilities)	0	(2,599)
Other Deferred Credits | Interest-rate contracts | Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	0
(Liabilities)	(241,624)	(111,780)
Other Assets [Member] | Interest-rate contracts | Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets		581
Interest-rate contracts | LIBOR Based Interest Payments [Member] | Cash Flow Hedging [Member] | Forward Contracts
Derivative, Fair Value [Line Items]
Derivative, Notional Amount	$ 1,300,000	$ 1,300,000

RISK MANAGEMENT AND HEDGING A_4

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES, Part 2 (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)MMcfMMBbls	Dec. 31, 2019USD ($)MMcfMMBbls
Derivative [Line Items]
Notional Amount Of Cash Flow Hedge Instruments Settled	$ 750
Designated as Hedging Instrument [Member] | Futures and swaps | - Natural gas (Bcf) | Fixed price | Purchased/ Payor
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMcf	0	0
Designated as Hedging Instrument [Member] | Futures and swaps | - Natural gas (Bcf) | Fixed price | Sold/ Receiver
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMcf	(47,600)	(59,000)
Designated as Hedging Instrument [Member] | Futures and swaps | - Natural gas (Bcf) | Basis | Purchased/ Payor
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMcf	0	0
Designated as Hedging Instrument [Member] | Futures and swaps | - Natural gas (Bcf) | Basis | Sold/ Receiver
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMcf	(47,600)	(59,000)
Designated as Hedging Instrument [Member] | Futures, forwards and swaps | - Crude oil and NGLs (MMBbl) | Fixed price | Purchased/ Payor
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBbls	10.5	7.9
Designated as Hedging Instrument [Member] | Futures, forwards and swaps | - Crude oil and NGLs (MMBbl) | Fixed price | Sold/ Receiver
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBbls	(17.5)	(17.4)
Designated as Hedging Instrument [Member] | Interest Rate Contract | Purchased/ Payor
Derivative [Line Items]
Derivative, Notional Amount	$ 2,400	$ 3,100
Designated as Hedging Instrument [Member] | Interest Rate Contract | Sold/ Receiver
Derivative [Line Items]
Derivative, Notional Amount	0	0
LIBOR Based Interest Payments [Member] | Cash Flow Hedging [Member] | Forward Contracts | Interest Rate Contract
Derivative [Line Items]
Derivative, Notional Amount	1,300	1,300
Forecasted Debt Issuances [Member] | Cash Flow Hedging [Member] | Forward Contracts | Interest Rate Contract
Derivative [Line Items]
Derivative, Notional Amount	1,100	$ 1,800
Notes Payable from Public Offering Due 2025, 2030 and 2050 [Member]
Derivative [Line Items]
Senior notes, noncurrent	$ 1,750

RISK MANAGEMENT AND HEDGING A_5

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES Part 3 (Details) - Cash Flow Hedging [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized change in fair value of cash flow hedges in other comprehensive income (loss)	$ (137,846)	$ (89,537)
Change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income (loss) on derivatives	19,682	16,348
Commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized change in fair value of cash flow hedges in other comprehensive income (loss)	87,195	(21,625)
Commodity contracts | Commodity sales revenues
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income (loss) on derivatives	44,999	23,822
Commodity contracts | Cost of sales and fuel
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income (loss) on derivatives	(15,039)	(4,970)
Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized change in fair value of cash flow hedges in other comprehensive income (loss)	(225,041)	(67,912)
Interest Rate Contract | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income (loss) on derivatives	$ (10,278)	$ (2,504)

DEBT DEBT (Details)

DEBT DEBT (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)Rate	Dec. 31, 2019USD ($)Rate
Debt Instrument [Line Items]
Total debt	$ 14,274,773	$ 12,813,704
Unamortized Portion of Terminated Swaps	14,603	15,032
Unamortized debt issuance costs and discounts	(135,076)	(121,329)
Current maturities of long-term debt	(7,650)	(7,650)
Short-term borrowings	0	(220,000)
Long-term debt	14,146,650	12,479,757
Repayments of Debt	50,500
Debt Instrument, Repurchased Face Amount	67,000
Gain (loss) on extinguishment of debt	$ 15,800
$2.5 Billion Credit Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant Description	Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in our $2.5 Billion Credit Agreement, adjusted for all noncash charges and increased for projected EBITDA from certain lender-approved capital expansion projects) of no more than 5.0 to 1 at March 31, 2020. At March 31, 2020, we had no borrowings outstanding, our ratio of indebtedness to adjusted EBITDA was 4.5 to 1, and we were in compliance with all covenants under our $2.5 Billion Credit Agreement.
Line of Credit Facility, Amount Outstanding	$ 0
Indebtedness To Adjusted Ebitda Current	4.5
Indebtedness To Adjusted EBITDA Maximum	5
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,500,000
Notes Payable from Public Offering Due 2025, 2030 and 2050 [Member]
Debt Instrument [Line Items]
Senior notes, noncurrent	1,750,000
Proceeds from Debt, Net of Issuance Costs	1,730,000
Guardian Pipeline [Member] | Notes Payables 1 due 2022 [Member]
Debt Instrument [Line Items]
Total debt	$ 19,395	21,307
Long-term Debt, Weighted Average Interest Rate, at Point in Time | Rate	7.85%
Subsidiary Issuer [Member] | 3.375% Notes Payable due 2022 [Member]
Debt Instrument [Line Items]
Total debt	$ 900,000	900,000
Interest Rate (in hundredths) | Rate	3.375%
Subsidiary Issuer [Member] | 5.0% Notes Payable due 2023 [Member]
Debt Instrument [Line Items]
Total debt	$ 425,000	425,000
Interest Rate (in hundredths) | Rate	5.00%
Subsidiary Issuer [Member] | 4.9% Notes Payable due 2025 [Member]
Debt Instrument [Line Items]
Total debt	$ 500,000	500,000
Interest Rate (in hundredths) | Rate	4.90%
Subsidiary Issuer [Member] | 6.65% Notes Payable due 2036 [Member]
Debt Instrument [Line Items]
Total debt	$ 600,000	600,000
Interest Rate (in hundredths) | Rate	6.65%
Subsidiary Issuer [Member] | 6.85% Notes Payable due 2037 [Member]
Debt Instrument [Line Items]
Total debt	$ 600,000	600,000
Interest Rate (in hundredths) | Rate	6.85%
Subsidiary Issuer [Member] | 6.125% Notes Payable due 2041 [Member]
Debt Instrument [Line Items]
Total debt	$ 650,000	650,000
Interest Rate (in hundredths) | Rate	6.125%
Subsidiary Issuer [Member] | 6.2% Notes Payable due 2043 [Member]
Debt Instrument [Line Items]
Total debt	$ 400,000	$ 400,000
Interest Rate (in hundredths) | Rate	6.20%
Parent Company
Debt Instrument [Line Items]
Short-term Debt, Weighted Average Interest Rate, at Point in Time | Rate	0.00%	2.16%
Commercial paper	$ 0	$ 220,000
Parent Company | Term Loan Agreement due 2021 [Member]
Debt Instrument [Line Items]
Total debt	1,250,000	1,250,000
Parent Company | 4.25% Notes Payable due 2022 [Member]
Debt Instrument [Line Items]
Total debt	$ 547,397	547,397
Interest Rate (in hundredths) | Rate	4.25%
Parent Company | 7.5% Notes Payable due 2023 [Member]
Debt Instrument [Line Items]
Total debt	$ 500,000	500,000
Interest Rate (in hundredths) | Rate	7.50%
Parent Company | 2.75% Notes Payable due 2024 [Member]
Debt Instrument [Line Items]
Total debt	$ 500,000	500,000
Interest Rate (in hundredths) | Rate	2.75%
Parent Company | 2.2% Notes Payable due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 400,000
Total debt	$ 397,000	0
Interest Rate (in hundredths) | Rate	2.20%
Parent Company | 4.0% Notes Payable due 2027 [Member]
Debt Instrument [Line Items]
Total debt	$ 500,000	500,000
Interest Rate (in hundredths) | Rate	4.00%
Parent Company | 4.55% Notes Payable due 2028 [Member]
Debt Instrument [Line Items]
Total debt	$ 800,000	800,000
Interest Rate (in hundredths) | Rate	4.55%
Parent Company | 6.875% Notes Payable due 2028 [Member]
Debt Instrument [Line Items]
Total debt	$ 100,000	100,000
Interest Rate (in hundredths) | Rate	6.875%
Parent Company | 4.35% Notes Payable due 2029 [Member]
Debt Instrument [Line Items]
Total debt	$ 700,000	700,000
Interest Rate (in hundredths) | Rate	4.35%
Parent Company | 3.4% Notes Payable due 2029 [Member]
Debt Instrument [Line Items]
Total debt	$ 734,251	750,000
Interest Rate (in hundredths) | Rate	3.40%
Parent Company | 3.1% Notes Payable due 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 850,000
Total debt	$ 821,050	0
Interest Rate (in hundredths) | Rate	3.10%
Parent Company | 6.0% Notes Payable due 2035 [Member]
Debt Instrument [Line Items]
Total debt	$ 400,000	400,000
Interest Rate (in hundredths) | Rate	6.00%
Parent Company | 4.95% Notes Payable due 2047 [Member]
Debt Instrument [Line Items]
Total debt	$ 693,405	700,000
Interest Rate (in hundredths) | Rate	4.95%
Parent Company | 5.2% Notes Payable due 2048 [Member]
Debt Instrument [Line Items]
Total debt	$ 1,000,000	1,000,000
Interest Rate (in hundredths) | Rate	5.20%
Parent Company | 4.45% Notes Payable due 2049 [Member]
Debt Instrument [Line Items]
Total debt	$ 747,650	750,000
Interest Rate (in hundredths) | Rate	4.45%
Parent Company | 4.5% Notes Payable due 2050 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000
Total debt	$ 489,625	$ 0
Interest Rate (in hundredths) | Rate	4.50%
Term Loan Agreement due 2021 [Member] | Parent Company
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,500,000

EQUITY (Details)

EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2019
Dividends, Per Share, Cash Paid		$ 0.935	$ 0.86
Dividends, Preferred Stock, Cash		$ 300
Preferred Stock, Dividends, Declared		$ 275	$ 275
Series E Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage		5.50%
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.935
Dividends Payable, Date of Record	Apr. 27, 2020
Dividends Payable, Date to be Paid	May 14, 2020
Preferred Stock, Dividends, Declared	$ 300

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Risk management assets/liabilities - January 1	$ (233,520)
Retirement and other postretirement benefit plan obligations - January 1	(131,481)
Risk-management assets/liabilities of unconsolidated affiliates - January 1	(8,999)
Accumulated other comprehensive loss - January 1	(374,000)
Other comprehensive income (loss) before reclassification, risk-management assets/liabilities	(106,141)	$ (68,944)
Other comprehensive (income) loss before reclassification, retirement and postretirement benefit plan obligations	20
Other comprehensive income (loss) before reclassification, risk-management assets/liabilities of unconsolidated affiliates	(7,777)
Other comprehensive income (loss) before reclassifications	(113,898)
Other comprehensive income (loss) reclassification adjustment from AOCI for risk-management assets/liabilities, net of tax	(15,164)	(12,171)
Other comprehensive (income) loss, retirement and other postretirement benefit plans, reclassification adjustment from AOCI, net of tax	3,542
Other comprehensive income (loss), reclassification adjustment from AOCI for other comprehensive income attributable to unconsolidated affiliates, net of tax	134
Other comprehensive income (loss), reclassification adjustment included in net income, net of tax	(11,488)
Other comprehensive income (loss), risk-management assets/liabilities, after reclassification adjustment, net of tax	(121,305)
Other comprehensive (income) loss, retirement and other postretirement benefit plans, after reclassification adjustment, net of tax	3,562	2,341
Other comprehensive income (loss), risk-management assets/liabilities of unconsolidated affiliates, net of tax	(7,643)	(2,511)
Other comprehensive income (loss), net of tax	(125,386)	$ (81,285)
Risk management assets/liabilities - March 31	(354,825)
Retirement and other postretirement benefit plan obligations - March 31	(127,919)
Risk-management assets/liabilities of unconsolidated affiliates - March 31	(16,642)
Accumulated other comprehensive loss - March 31	(499,386)
Price risk cash flow hedge unrealized gain (loss) to be reclassified during next 12 months	73,000
Commodity cash flow hedge gain (loss) to be reclassified after next 12 months net	(800)
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net	(29,400)
Cash Flow Hedging [Member] | Commodity contracts
Unrealized gain loss on cash flow hedges net of tax accumulated other comprehensive income loss	72,180
Cash Flow Hedging [Member] | Interest Rate Contract
Amount of accumulated other comprehensive income (loss) attributable primarily to settled interest-rate swaps.	(218,877)
Cash Flow Hedging [Member] | Forward Contracts
Amount of accumulated other comprehensive income (loss) attributable primarily to forward starting interest-rate swaps.	$ (208,128)

EARNINGS PER SHARE EARNINGS P_3

EARNINGS PER SHARE EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Basic EPS
Net income (loss) available for common stock	$ (142,132)	$ 336,933
Shares	414,282	412,908
Earnings (loss) per share, basic	$ (0.34)	$ 0.82
Diluted EPS
Effect of dilutive securities	$ 0	$ 0
Effect of dilutive securities, number of shares	1,066	2,325
Net income (loss) available for common stock and common stock equivalents	$ (142,132)	$ 336,933
Shares	415,348	415,233
Earnings (loss) per share, diluted	$ (0.34)	$ 0.81

EMPLOYEE BENEFIT PLANS EMPLOY_3

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income tax benefits reclassified from accumulated other comprehensive loss to income tax (expense) benefit
Income tax benefit	$ 1,100	$ 700
Retirement Benefits
Components of net periodic benefit cost
Service cost	2,036	1,954
Interest cost	4,574	5,126
Expected return on plan assets	(6,232)	(5,892)
Amortization of net loss	4,571	3,158
Amortization of prior service cost (credit) (a)	28	0
Net periodic benefit cost (income)	4,977	4,346
Other Postretirement Benefits Plan
Components of net periodic benefit cost
Service cost	115	117
Interest cost	442	509
Expected return on plan assets	(722)	(570)
Amortization of net loss	1	74
Amortization of prior service cost (credit) (a)	0	(57)
Net periodic benefit cost (income)	$ (164)	$ 73

UNCONSOLIDATED AFFILIATES (Deta

UNCONSOLIDATED AFFILIATES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	$ 44,627	$ 43,481
Accounts Payable, Related Parties, Current	14,700		$ 13,500
Impairment of equity investments	(37,730)	0
Equity-method goodwill	16,500
Unconsolidated Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction, Expenses from Transactions with Related Parties	45,300	41,800
Northern Border Pipeline
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	22,120	20,802
Overland Pass Pipeline
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	14,111	17,394
Roadrunner
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	6,433	6,338
Other Unconsolidated Affiliates
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	1,963	$ (1,053)
Natural Gas Liquids | Chisholm Pipeline Company [Member]
Schedule of Equity Method Investments [Line Items]
Impairment of equity investments	$ (7,200)
Equity Method Investment, Ownership Percentage	50.00%
Natural Gas Gathering And Processing [Member] | Venice Energy Services Company [Member]
Schedule of Equity Method Investments [Line Items]
Impairment of equity investments	$ (30,500)
Equity Method Investment, Ownership Percentage	10.20%
Impairment of equity investments - goodwill	$ (22,300)

LEASES (Details)

LEASES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020
Lessee, Operating Lease, Details [Line Items]
Operating cash flows for operating leases	$ 2,840	$ 1,519
Financing cash flows for finance lease	469	425
Right-of-use assets obtained in exchange for operating lease liabilities (noncash)	97,339	$ 380
Lease remaining balance related to lease entered in December 2019 [Member] [Member] [Member]
Lessee, Operating Lease, Details [Line Items]
Lease liability remaining balance	74,200
Right-of-use asset remaining balance	74,000
Term of contract			10 years
Certain Operating Leases Entered Into During The Period [Member]
Lessee, Operating Lease, Details [Line Items]
Lease liability remaining balance	17,200
Right-of-use asset remaining balance	$ 17,200
Weighted-Average Remaining Lease Term [Member]
Lessee, Operating Lease, Details [Line Items]
Operating Lease, Weighted Average Remaining Lease Term	8 years 9 months 18 days
Weighted-Average Discount Rate [Member]
Lessee, Operating Lease, Details [Line Items]
Operating Lease, Weighted Average Discount Rate, Percent	3.15%
Maturity of Finance Lease Liability
Lessee, Operating Lease, Details [Line Items]
Remainder of 2020	$ 3,400
2021	4,500
2022	4,500
2023	4,500
2024	4,500
2025 and beyond	17,100
Total lease payments	38,500
Less: Interest	12,700
Present value of lease liabilities	25,800
Maturity of Operating Lease Liabilities
Lessee, Operating Lease, Details [Line Items]
Remainder of 2020	12,400
2021	16,300
2022	14,900
2023	13,700
2024	12,400
2025 and beyond	57,000
Total lease payments	126,700
Less: Interest	16,800
Lease liability remaining balance	$ 109,900

REVENUE REVENUE (Details)

REVENUE REVENUE (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Contract with Customer, Liability [Abstract]
Contract with customer, liability	$ 45.7	$ 57.1
Revenue recognized included in beginning balance	(18.2)
Net additions	6.8
Contract with Customer, Liability, Current	11.9	22.2
Contract with Customer, Liability, Noncurrent	33.8	$ 34.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 1,831.9
Remaining Contract Terms [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Performance Obligation, Contract Term	one month to 24 years
2020 [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 257.2
2021 [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	305.3
2022 [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	230.9
2023 [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	184.6
Thereafter [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 853.9

SEGMENTS (Details)

SEGMENTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Segment disclosure [Abstract]
Revenues	$ 2,136,672	$ 2,779,958
Cost of sales and fuel (exclusive of depreciation and operating costs)	(1,276,928)	(1,956,377)
Operating costs	(207,040)	(240,741)
Equity in net earnings (loss) from investments	44,627	43,481
Depreciation and amortization	(132,353)	(114,158)
Impairment charges	(641,754)	0
Investments in unconsolidated affiliates	810,479	950,924	$ 861,844
Total assets	21,969,440	18,934,325	$ 21,812,121
Capital expenditures	949,679	889,705
Net income (loss)	(141,857)	337,208
Interest expense, net of capitalized interest	140,616	115,420
Income tax expense (benefit)	(55,395)	77,934
Noncash compensation expense	(1,302)	5,540
Other corporate costs and noncash items	(33,081)	(13,729)
Gain (loss) on extinguishment of debt	15,800
Natural Gas Gathering And Processing [Member]
Segment disclosure [Abstract]
Revenues	449,980	694,661
Cost of sales and fuel (exclusive of depreciation and operating costs)	(202,170)	(450,913)
Operating costs	(84,470)	(94,247)
Equity in net earnings (loss) from investments	806	(1,202)
Noncash compensation expense and other	(4,498)	3,945
Segment adjusted EBITDA	159,648	152,244
Depreciation and amortization	(58,756)	(52,681)
Impairment charges	(564,353)
Investments in unconsolidated affiliates	4,276	39,749
Total assets	6,374,552	6,208,883
Capital expenditures	181,610	215,148
Natural Gas Gathering And Processing [Member] | Natural Gas Gathering and Processing Intersegment [Member]
Segment disclosure [Abstract]
Revenues	213,300	335,800
Natural Gas Liquids
Segment disclosure [Abstract]
Revenues	1,770,592	2,311,500
Cost of sales and fuel (exclusive of depreciation and operating costs)	(1,278,754)	(1,846,673)
Operating costs	(89,571)	(110,438)
Equity in net earnings (loss) from investments	15,268	17,544
Noncash compensation expense and other	(6,619)	5,706
Segment adjusted EBITDA	410,916	377,639
Depreciation and amortization	(57,841)	(46,401)
Impairment charges	(77,401)
Investments in unconsolidated affiliates	435,024	447,272
Total assets	12,682,807	10,220,412
Capital expenditures	746,183	639,338
Natural Gas Liquids | Natural Gas Liquids Regulated [Member]
Segment disclosure [Abstract]
Revenues	435,100	323,100
Cost of sales and fuel (exclusive of depreciation and operating costs)	(120,400)	(118,500)
Natural Gas Pipelines
Segment disclosure [Abstract]
Revenues	120,783	116,400
Cost of sales and fuel (exclusive of depreciation and operating costs)	(1,539)	(1,755)
Operating costs	(33,307)	(36,268)
Equity in net earnings (loss) from investments	28,553	27,139
Noncash compensation expense and other	(1,966)	1,132
Segment adjusted EBITDA	112,524	106,648
Depreciation and amortization	(14,769)	(14,156)
Impairment charges	0
Investments in unconsolidated affiliates	371,179	463,903
Total assets	2,089,362	2,138,759
Capital expenditures	16,590	28,688
Natural Gas Pipelines | Natural Gas Pipelines Regulated [Member]
Segment disclosure [Abstract]
Revenues	73,900	70,100
Cost of sales and fuel (exclusive of depreciation and operating costs)	(6,100)	(5,600)
Total Segments [Member]
Segment disclosure [Abstract]
Revenues	2,341,355	3,122,561
Cost of sales and fuel (exclusive of depreciation and operating costs)	(1,482,463)	(2,299,341)
Operating costs	(207,348)	(240,953)
Equity in net earnings (loss) from investments	44,627	43,481
Noncash compensation expense and other	(13,083)	10,783
Segment adjusted EBITDA	683,088	636,531
Depreciation and amortization	(131,366)	(113,238)
Impairment charges	(641,754)
Investments in unconsolidated affiliates	810,479	950,924
Total assets	21,146,721	18,568,054
Capital expenditures	944,383	883,174
Other and Eliminations
Segment disclosure [Abstract]
Revenues	(204,683)	(342,603)
Cost of sales and fuel (exclusive of depreciation and operating costs)	205,535	342,964
Operating costs	308	212
Equity in net earnings (loss) from investments	0	0
Depreciation and amortization	(987)	(920)
Impairment charges	0
Investments in unconsolidated affiliates	0	0
Total assets	822,719	366,271
Capital expenditures	5,296	6,531
Operating Segments [Member] | Natural Gas Liquids | Natural Gas Liquids Regulated [Member]
Segment disclosure [Abstract]
Revenues	378,200	270,000
Noncustomer [Domain]
Segment disclosure [Abstract]
Revenues	80,200	22,300
NGL and Condensate Sales [Member]
Segment disclosure [Abstract]
Revenues	1,617,156	2,152,084
NGL and Condensate Sales [Member] | Natural Gas Gathering And Processing [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	219,917	332,332
NGL and Condensate Sales [Member] | Natural Gas Liquids
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,596,711	2,158,103
NGL and Condensate Sales [Member] | Natural Gas Pipelines
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0
NGL and Condensate Sales [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,816,628	2,490,435
NGL and Condensate Sales [Member] | Other and Eliminations
Segment disclosure [Abstract]
Revenues	(199,472)	(338,351)
Residue Natural Gas Sales [Member]
Segment disclosure [Abstract]
Revenues	190,054	320,006
Residue Natural Gas Sales [Member] | Natural Gas Gathering And Processing [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	189,051	319,036
Residue Natural Gas Sales [Member] | Natural Gas Liquids
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0
Residue Natural Gas Sales [Member] | Natural Gas Pipelines
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,035	970
Residue Natural Gas Sales [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	191,086	320,006
Residue Natural Gas Sales [Member] | Other and Eliminations
Segment disclosure [Abstract]
Revenues	(1,032)	0
Gathering, Processing and Exchange Services Revenue
Segment disclosure [Abstract]
Revenues	158,473	138,276
Gathering, Processing and Exchange Services Revenue | Natural Gas Gathering And Processing [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	37,937	39,742
Gathering, Processing and Exchange Services Revenue | Natural Gas Liquids
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	120,536	98,534
Gathering, Processing and Exchange Services Revenue | Natural Gas Pipelines
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0
Gathering, Processing and Exchange Services Revenue | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	158,473	138,276
Gathering, Processing and Exchange Services Revenue | Other and Eliminations
Segment disclosure [Abstract]
Revenues	0	0
Transportation and Storage Revenue [Member]
Segment disclosure [Abstract]
Revenues	165,310	161,250
Transportation and Storage Revenue [Member] | Natural Gas Gathering And Processing [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0
Transportation and Storage Revenue [Member] | Natural Gas Liquids
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	50,755	52,322
Transportation and Storage Revenue [Member] | Natural Gas Pipelines
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	118,364	112,865
Transportation and Storage Revenue [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	169,119	165,187
Transportation and Storage Revenue [Member] | Other and Eliminations
Segment disclosure [Abstract]
Revenues	(3,809)	(3,937)
Other [Member]
Segment disclosure [Abstract]
Revenues	5,679	8,342
Other [Member] | Natural Gas Gathering And Processing [Member]
Segment disclosure [Abstract]
Revenues	3,075	3,551
Other [Member] | Natural Gas Liquids
Segment disclosure [Abstract]
Revenues	2,590	2,541
Other [Member] | Natural Gas Pipelines
Segment disclosure [Abstract]
Revenues	384	2,565
Other [Member] | Total Segments [Member]
Segment disclosure [Abstract]
Revenues	6,049	8,657
Other [Member] | Other and Eliminations
Segment disclosure [Abstract]
Revenues	$ (370)	$ (315)