ONEOK (OKE) 10-K 25 Feb 14 2013 FY Annual report Financial data

Document_And_Entity_Informatio

Document And Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2013	Feb. 19, 2014	Jun. 30, 2013
Document Information [Line Items]	'	'	'
Entity Registrant Name	'ONEOK INC /NEW/	'	'
Entity Central Index Key	'0001039684	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Public Float	'	'	$8.10
Entity Common Stock, Shares Outstanding	'	207,814,086	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]	'	'	'
Revenues	$14,602,717	$12,632,559	$14,805,794
Cost of sales and fuel	12,313,034	10,281,718	12,425,435
Net margin	2,289,683	2,350,841	2,380,359
Operating expenses	'	'	'
Operations and maintenance	872,125	806,087	813,666
Depreciation and amortization	384,377	335,844	312,160
Goodwill impairment	0	10,255	0
General taxes	118,328	102,891	94,657
Total operating expenses	1,374,830	1,255,077	1,220,483
Gain (loss) on sale of assets	11,881	6,736	-963
Operating income	926,734	1,102,500	1,158,913
Equity earnings from investments (Note P)	110,517	123,024	127,246
Allowance for equity funds used during construction	30,522	13,648	2,335
Other income	24,483	12,504	1,410
Other expense	-17,707	-4,925	-9,336
Interest expense (net of capitalized interest of $57,775, $41,776 and $23,960, respectively)	-334,206	-302,305	-297,006
Income before income taxes	740,343	944,446	983,562
Income taxes (Note O)	-163,382	-215,195	-226,048
Income from continuing operations	576,961	729,251	757,514
Income from discontinued operations, net of tax (Note C)	0	762	2,230
Gain on sale of discontinued operations, net of tax (Note C)	0	13,517	0
Net income	576,961	743,530	759,744
Less: Net income attributable to noncontrolling interests	310,428	382,911	399,150
Net income attributable to ONEOK	266,533	360,619	360,594
Amounts attributable to ONEOK:	'	'	'
Income from continuing operations	266,533	346,340	358,364
Income from discontinued operations	0	14,279	2,230
Net Income	$266,533	$360,619	$360,594
Basic earnings per share:	'	'	'
Income from continuing operations (Note L)	$1.29	$1.68	$1.71
Income from discontinued operations	$0	$0.07	$0.01
Net Income	$1.29	$1.75	$1.72
Diluted earnings per share:	'	'	'
Income from continuing operations (Note L)	$1.27	$1.64	$1.67
Income from discontinued operations	$0	$0.07	$0.01
Net Income	$1.27	$1.71	$1.68
Average shares (thousands)	'	'	'
Basic	206,044	206,140	209,344
Diluted	209,695	210,710	214,498
Dividends declared per share of common stock	$1.48	$1.27	$1.08

CONSOLIDATED_STATEMENTS_OF_INC1

CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Interest Costs, Capitalized During Period	$57,775	$41,776	$23,960

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Other Comprehensive Income [Abstract]	'	'	'
Net income	$576,961	$743,530	$759,744
Other comprehensive income (loss), net of tax	'	'	'
Unrealized gains (losses) on energy marketing and risk management assets/liabilities, net of tax of $(5,574), $(10,061) and $(8,670), respectively	25,609	22,826	-19,828
Realized (gains) losses in net income, net of tax of $(1,905), $10,327 and $53,714, respectively	7,926	-49,499	-84,025
Unrealized holding gains (losses) on available-for-sale securities, net of tax of $112, $(30) and $242, respectively	-177	47	-384
Change in pension and postretirement benefit plan liability, net of tax of $(52,436), $6,977 and $16,298, respectively	83,126	-11,061	-25,837
Other, net of tax of $0, $0 and $50, respectively	0	0	-79
Total other comprehensive income (loss), net of tax	116,484	-37,687	-130,153
Comprehensive income	693,445	705,843	629,591
Less: Comprehensive income attributable to noncontrolling interests	332,101	355,901	366,316
Comprehensive income attributable to ONEOK	$361,344	$349,942	$263,275

CONSOLIDATED_STATEMENTS_OF_COM1

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Other Comprehensive Income [Abstract]	'	'	'
Unrealized gain (losses) on energy marketing and risk management assets/liabilities, tax	($5,574)	($10,601)	($8,670)
Realized (gains) losses in net income, tax	-1,905	10,327	53,714
Unrealized holding gains (losses) on available-for-sale securities, tax	112	-30	242
Change in pension and postretirement benefit plan liability, tax	-52,436	6,977	16,298
Other, tax	$0	$0	$50

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets	'	'
Cash and cash equivalents	$149,313	$583,618
Accounts receivable, net	1,549,563	1,349,371
Gas and natural gas liquids in storage	417,077	517,014
Commodity imbalances	82,144	90,211
Energy marketing and risk management assets (Notes D and E)	1,687	48,577
Other current assets	171,018	175,869
Total current assets	2,370,802	2,764,660
Property, plant and equipment	'	'
Property, plant and equipment	15,536,156	13,088,991
Accumulated depreciation and amortization	3,238,652	2,974,651
Net property, plant and equipment (Note F)	12,297,504	10,114,340
Investments and other assets	'	'
Investments in unconsolidated affiliates (Note P)	1,229,838	1,221,405
Goodwill and intangible assets (Note G)	1,182,515	996,206
Other assets	626,899	758,664
Total investments and other assets	3,039,252	2,976,275
Total assets	17,707,558	15,855,275
Current liabilities	'	'
Current maturities of long-term debt (Note I)	10,656	10,855
Notes payable (Note H)	564,462	817,170
Accounts payable	1,503,699	1,333,489
Commodity imbalances	212,136	272,436
Energy marketing and risk management liabilities (Notes D and E)	4,032	9,990
Other current liabilities	401,422	369,054
Total current liabilities	2,696,407	2,812,994
Long-term debt, excluding current maturities (Note I)	7,754,975	6,515,372
Deferred credits and other liabilities	'	'
Deferred income taxes (Note O)	1,938,262	1,592,802
Other deferred credits	472,734	701,657
Total deferred credits and other liabilities	2,410,996	2,294,459
Commitments and contingencies (Note R)	'	'
ONEOK shareholders' equity:	'	'
Common stock, $0.01 par value: authorized 600,000,000 shares; issued 245,811,180 shares and outstanding 206,618,877 shares at December 31, 2013; issued 245,811,180 shares and outstanding 204,935,043 shares at December 31, 2012	2,458	2,458
Paid-in capital	1,433,600	1,324,698
Accumulated other comprehensive loss (Note K)	-121,987	-216,798
Retained earnings	2,020,815	2,059,024
Treasury stock, at cost: 39,192,303 shares at December 31, 2013 and 40,876,137 shares at December 31, 2012	-997,035	-1,039,773
Total ONEOK shareholders' equity	2,337,851	2,129,609
Noncontrolling interests in consolidated subsidiaries	2,507,329	2,102,841
Total equity	4,845,180	4,232,450
Total liabilities and equity	$17,707,558	$15,855,275

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS Parenthetical (USD $)	Dec. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]	'	'
Common stock, shares, par value (in dollars per share)	$0.01	$0.01
Common stock, shares, authorized (in shares)	600,000,000	600,000,000
Common stock, shares, issued (in shares)	245,811,180	245,811,180
Common stock, shares, outstanding (in shares)	206,618,877	204,935,043
Treasury stock, shares (in shares)	39,192,203	40,876,137

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities	'	'	'
Net income	$576,961	$743,530	$759,744
Adjustments to reconcile net income to net cash provided by operating activities:	'	'	'
Depreciation and amortization	384,377	335,852	312,288
Charges attributable to exit activities, net of settlements	121,971	0	0
Impairment of goodwill	0	10,255	0
Gain on sale of discontinued operations	0	-13,517	0
Equity earnings from investments	-110,517	-123,024	-127,246
Distributions received from unconsolidated affiliates	106,364	120,442	132,741
Deferred income taxes	151,515	229,398	256,688
Share-based compensation expense	46,194	36,692	66,371
Pension and other postretirement benefit expense, net of contributions	56,600	-57,073	-29,863
Allowance for equity funds used during construction	-30,522	-13,648	-2,335
Loss (gain) on sale of assets	-11,881	-6,736	963
Other	-5,656	27,982	-1,471
Changes in assets and liabilities:	'	'	'
Accounts receivable	-189,809	-14,774	-55,861
Gas and natural gas liquids in storage	99,937	33,343	65,845
Accounts payable	165,076	-30,981	102,621
Commodity imbalances, net	-52,233	43,471	-54,886
Energy marketing and risk management assets and liabilities	25,072	-174,953	-31,999
Other assets and liabilities	-38,682	-162,264	-37,434
Cash provided by operating activities	1,294,767	983,995	1,356,166
Investing Activities	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	-2,256,585	-1,866,153	-1,336,067
Acquisitions	-394,889	0	0
Proceeds from sale of discontinued operations, net of cash sold	0	32,946	0
Contributions to unconsolidated affiliates	-35,308	-30,768	-64,491
Distributions received from unconsolidated affiliates	31,134	35,299	23,644
Proceeds from sale of assets	13,617	12,240	1,288
Other	0	2,237	4,000
Cash used in investing activities	-2,642,031	-1,814,199	-1,371,626
Financing Activities	'	'	'
Borrowing (repayment) of notes payable, net	-252,708	-24,812	285,127
Issuance of debt, net of discounts	1,247,822	1,994,693	1,295,450
Long-term debt financing costs	-10,246	-15,036	-10,986
Repayment of debt	-7,868	-361,464	-727,562
Repurchase of common stock	0	-150,000	-300,108
Issuance of common stock	20,602	15,969	17,906
Issuance of common units, net of issuance costs	583,929	459,587	0
Dividends paid	-304,742	-261,969	-227,020
Distributions to noncontrolling interests	-374,142	-324,906	-277,375
Excess tax benefit from stock-based awards	10,312	6,948	3,806
Cash provided by financing activities	912,959	1,339,010	59,238
Change in cash and cash equivalents	-434,305	508,806	43,778
Change in cash and cash equivalents included in discontinued operations	0	8,859	-8,166
Change in cash and cash equivalents from continuing operations	-434,305	517,665	35,612
Cash and cash equivalents at beginning of period	583,618	65,953	30,341
Cash and cash equivalents at end of period	149,313	583,618	65,953
Supplemental cash flow information:	'	'	'
Cash paid for interest, net of amounts capitalized	294,240	439,398	278,162
Cash paid (refunds received) for income taxes	($16,640)	$872	($68,696)

CONSOLIDATED_STATEMENT_OF_CHAN

CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY (USD $)	Total	Common Stock [Member]	Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Noncontrolling Interests in Consolidated Subsidiaries [Member]
In Thousands, except Share data
Shareholders' equity, beginning balance at Dec. 31, 2010	$3,920,841	$2,456	$1,391,443	($108,802)	$1,826,800	($663,274)	$1,472,218
Common stock issued, beginning balance (in shares) at Dec. 31, 2010	'	245,631,272	'	'	'	'	'
Net income	759,744	0	0	0	360,594	0	399,150
Other comprehensive income (loss)	-130,153	0	0	-97,319	0	0	-32,834
Repurchase of common stock	-300,108	0	0	0	0	-300,108	0
Common stock issued (in shares)	'	178,576	'	'	'	'	'
Common stock issued	53,803	2	25,742	0	0	28,059	0
Common stock dividends - $1.08, $1.27, and $1.48 per share	-227,020	0	0	0	-227,020	0	0
Distributions to noncontrolling interests	-277,375	0	0	0	0	0	-277,375
Shareholders' equity, ending balance at Dec. 31, 2011	3,799,732	2,458	1,417,185	-206,121	1,960,374	-935,323	1,561,159
Common stock issued, ending balance (in shares) at Dec. 31, 2011	'	245,809,848	'	'	'	'	'
Net income	743,530	0	0	0	360,619	0	382,911
Other comprehensive income (loss)	-37,687	0	0	-10,677	0	0	-27,010
Repurchase of common stock	-150,000	0	0	0	0	-150,000	0
Common stock issued (in shares)	'	1,332	'	'	'	'	'
Common stock issued	22,146	0	-23,404	0	0	45,550	0
Common stock dividends - $1.08, $1.27, and $1.48 per share	-261,969	0	0	0	-261,969	0	0
Issuance of common units of ONEOK Partners	459,587	0	-51,100	0	0	0	510,687
Distributions to noncontrolling interests	-324,906	0	0	0	0	0	-324,906
Other	-17,983	0	-17,983	0	0	0	0
Shareholders' equity, ending balance at Dec. 31, 2012	4,232,450	2,458	1,324,698	-216,798	2,059,024	-1,039,773	2,102,841
Common stock issued, ending balance (in shares) at Dec. 31, 2012	'	245,811,180	'	'	'	'	'
Net income	576,961	0	0	0	266,533	0	310,428
Other comprehensive income (loss)	116,484	0	0	94,811	0	0	21,673
Common stock issued (in shares)	'	0	'	'	'	'	'
Common stock issued	26,189	0	-16,549	0	0	42,738	0
Common stock dividends - $1.08, $1.27, and $1.48 per share	-304,742	0	0	0	-304,742	0	0
Issuance of common units of ONEOK Partners	533,824	0	87,295	0	0	0	446,529
Distributions to noncontrolling interests	-374,142	0	0	0	0	0	-374,142
Other	38,156	0	38,156	0	0	0	0
Shareholders' equity, ending balance at Dec. 31, 2013	$4,845,180	$2,458	$1,433,600	($121,987)	$2,020,815	($997,035)	$2,507,329
Common stock issued, ending balance (in shares) at Dec. 31, 2013	'	245,811,180	'	'	'	'	'

CONSOLIDATED_STATEMENT_OF_CHAN1

CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Stockholders' Equity [Abstract]	'	'	'	'
Dividends declared per share of common stock	$0.40	$1.48	$1.27	$1.08

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	'
	A.	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Organization and Nature of Operations - We are a diversified energy company and successor to the company founded in 1906 known as Oklahoma Natural Gas Company.  We are a corporation incorporated under the laws of the state of Oklahoma, and our common stock is listed on the NYSE under the trading symbol “OKE.”  We are the sole general partner and own 41.2 percent of ONEOK Partners, L.P. (NYSE: OKS), one of the largest publicly traded master limited partnerships.
	At December 31, 2013, we have divided our operations into three reportable business segments as follows:
	•	ONEOK Partners;
	•	Natural Gas Distribution; and
	•	Energy Services.
	On January 31, 2014, we completed the separation of our natural gas distribution business into a standalone publicly traded company, ONE Gas. In addition, we expect to complete an accelerated wind down of our Energy Services business on March 31, 2014. ONEOK and its subsidiaries will continue to be the sole general partner and own 41.2 percent of ONEOK Partners as of December 31, 2013. Following the separation of the natural gas distribution business and the wind down of our energy services business, our cash flows will be derived from the cash distributions we receive from ONEOK Partners associated with our limited and general partner interests, including incentive distribution rights. See Note U for additional discussion of the separation of the natural gas distribution business. See Note B for additional discussion of the exit activities associated with the wind down of the energy services business.
	ONEOK Partners is a publicly traded master limited partnership involved in the gathering, processing, storage and transportation of natural gas in the United States.  In addition, ONEOK Partners owns one of the nation’s premier natural gas liquids systems, connecting NGL supply in the Mid-Continent and Rocky Mountain regions with key market centers.  To aid in understanding the important business and financial characteristics of our ONEOK Partners segment, the following describes its business with reference to its underlying activities.
	ONEOK Partners gathers and/or processes natural gas in two producing basins in the Rocky Mountain region: the Williston Basin, which spans portions of Montana and North Dakota and includes the oil-producing, NGL-rich Bakken Shale and Three Forks formations; and the Powder River Basin of Wyoming, which includes the NGL-rich Frontier, Turner, Sussex and Niobrara Shale formations.  Coal-bed methane, or dry natural gas, in the Powder River Basin does not require processing or NGL extraction in order to be marketable; dry natural gas is gathered, compressed and delivered into a downstream pipeline or marketed for a fee. ONEOK Partners also gathers and processes natural gas in the Mid-Continent region, which includes the NGL-rich Cana-Woodford Shale, Woodford Shale, Granite Wash area and the Mississippian Lime formation of Oklahoma and Kansas and the Hugoton and Central Kansas Uplift Basins of Kansas.  The natural gas ONEOK Partners gathers from its Sage Creek plant contains NGL-rich natural gas from the Niobrara Shale area of the Powder River Basin.
	ONEOK Partners’ natural gas liquids business consists of facilities that gather, fractionate and treat NGLs and store NGL products primarily in Oklahoma, Kansas, Texas and the Rocky Mountain region where it provides nondiscretionary services to producers for NGLs.  Its natural gas liquids business owns or has an ownership interest in FERC-regulated natural gas liquids gathering and distribution pipelines in Oklahoma, Kansas, Texas, Wyoming, Colorado, North Dakota and Montana, and terminal and storage facilities in Missouri, Nebraska, Iowa and Illinois.  It also owns FERC-regulated natural gas liquids distribution and refined petroleum products pipelines in Kansas, Missouri, Nebraska, Iowa, Illinois and Indiana that connect its Mid-Continent assets with Midwest markets, including Chicago, Illinois.  ONEOK Partners’ natural gas liquids business also owns and operates truck- and rail-loading and -unloading facilities that interconnect with its NGL fractionation and pipeline assets.
	ONEOK Partners’ natural gas pipeline business operates interstate and intrastate natural gas transmission pipelines and natural gas storage facilities.  ONEOK Partners’ FERC-regulated interstate assets transport natural gas through pipelines in North Dakota, Minnesota, Wisconsin, Illinois, Indiana, Kentucky, Tennessee, Oklahoma, Texas and New Mexico.  ONEOK Partners’ intrastate natural gas pipeline assets are located in Oklahoma, Texas and Kansas, and have access to major natural gas producing areas in those states, including the Cana-Woodford, Woodford Shale, Granite Wash and Mississippian Lime areas.  ONEOK Partners owns underground natural gas storage facilities in Oklahoma and Texas, which are connected to its intrastate natural gas pipeline assets, as well as underground natural gas storage facilities in Kansas.
	Our former Natural Gas Distribution segment provides natural gas distribution services to more than 2 million customers in Oklahoma, Kansas and Texas through Oklahoma Natural Gas, Kansas Gas Service and Texas Gas Service. The natural gas utilities serve residential, commercial, industrial and transportation customers in all three states.  In addition, the natural gas distribution companies serve wholesale and public authority customers.
	Our Energy Services segment is a provider of nonuniform natural gas supply and risk-management services for natural gas and electric utilities and industrial customers with natural gas needs.  We use a network of leased storage and transportation capacity to supply natural gas to our customers.  This network connects major supply and demand centers and, coupled with our industry knowledge and market intelligence, allows us to provide our customers with customized services in a more efficient and reliable manner than they can achieve independently. Our customers are primarily LDCs, electric utilities and industrial end-users.  Our customers’ natural gas needs vary with seasonal changes in weather and are therefore somewhat unpredictable.
	Consolidation - Our consolidated financial statements include the accounts of ONEOK and our subsidiaries over which we have control or are the primary beneficiary.  We have recorded noncontrolling interests in consolidated subsidiaries on our Consolidated Balance Sheets to recognize the portion of ONEOK Partners that we do not own.  We reflected our ownership interest in ONEOK Partners’ accumulated other comprehensive income (loss) in our consolidated accumulated other comprehensive income (loss).  The remaining portion is reflected as an adjustment to noncontrolling interests in consolidated subsidiaries.  All significant intercompany balances and transactions have been eliminated in consolidation. We have recast prior period amounts in the Consolidated Statements of Cash Flows to revise the classification of the excess tax benefit of share-based compensation to financing from operating activities.
	Investments in unconsolidated affiliates are accounted for using the equity method if we have the ability to exercise significant influence over operating and financial policies of our investee. Under this method, an investment is carried at its acquisition cost and adjusted each period for contributions made, distributions received and our share of the investee’s comprehensive income. For the investments we account for under the equity method, the premium or excess cost over underlying fair value of net assets is referred to as equity method goodwill. Impairment of equity investments is recorded when the impairments are other than temporary. These amounts are recorded as investments in unconsolidated affiliates on our accompanying Consolidated Balance Sheets. Distributions paid to us from our unconsolidated affiliates are classified as operating activities on our Consolidated Statements of Cash Flows until the cumulative distributions exceed our proportionate share of income from the unconsolidated affiliate since the date of our initial investment.  The amount of cumulative distributions paid to us that exceeds our cumulative proportionate share of income in each period represents a return of investment and is classified as an investing activity on our Consolidated Statements of Cash Flows. See Note P for disclosures of our unconsolidated affiliates.
	Use of Estimates - The preparation of our consolidated financial statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amount of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements.  These estimates and assumptions also affect the reported amounts of revenue and expenses during the reporting period.  Items that may be estimated include, but are not limited to, the economic useful life of assets, fair value of assets and liabilities, obligations under employee benefit plans, provisions for uncollectible accounts receivable, unbilled revenues for natural gas delivered but for which meters have not been read, gas purchased expense for natural gas purchased but for which no invoice has been received, provision for income taxes, including any deferred tax valuation allowances, the results of litigation and various other recorded or disclosed amounts.
	We evaluate these estimates on an ongoing basis using historical experience, consultation with experts and other methods we consider reasonable based on the particular circumstances.  Nevertheless, actual results may differ significantly from the estimates. Any effects on our financial position or results of operations from revisions to these estimates are recorded in the period when the facts that give rise to the revision become known.
	Fair Value Measurements - We define fair value as the price that would be received from the sale of an asset or the transfer of a liability in an orderly transaction between market participants at the measurement date.  We use the market and income approaches to determine the fair value of our assets and liabilities and consider the markets in which the transactions are executed. 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.
	While many of the contracts in our portfolio are executed in liquid markets where price transparency exists, some contracts are executed in markets for which market prices may exist, but the market may be relatively inactive.  This results in limited price transparency that requires management’s judgment and assumptions to estimate fair values.  Inputs into our fair value estimates include commodity-exchange prices, over-the-counter quotes, volatility, historical correlations of pricing data and LIBOR and other liquid money-market instrument rates.  We also utilize internally developed basis curves that incorporate observable and unobservable market data.  We validate our valuation inputs with third-party information and settlement prices from other sources, where available.
	In addition, as prescribed by the income approach, 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 LIBOR, Eurodollar futures and interest-rate swaps.  We also take into consideration the potential impact on market prices of liquidating positions in an orderly manner over a reasonable period of time under current market conditions.  We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using specific and sector bond yields and also monitor the credit default swap markets.  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 from our estimates, and the differences could be material.
	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.
	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 - Unadjusted quoted prices in active markets for identical assets or liabilities;
	•	Level 2 - Significant observable pricing inputs other than quoted prices included within Level 1 that are, either directly or indirectly, observable as of the reporting date.  Essentially, this represents inputs that are derived principally from or corroborated by observable market data; and
	•	Level 3 - May include one or more unobservable inputs that are significant in establishing a fair value estimate.  These unobservable inputs are developed based on the best information available and may include our own internal data.
	We recognize transfers into and out of Level 3 as of the end of each reporting period.  Transfers into Level 3 represent existing assets or liabilities that were categorized previously at a higher level for which the unobservable inputs became a more significant portion of the fair value estimates. Transfers out of Level 3 represent existing assets and liabilities that were classified previously as Level 3 for which the observable inputs became a more significant portion of the fair value estimates.
	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.  See Note D for additional disclosures of our fair value measurements.
	Cash and Cash Equivalents - Cash equivalents consist of highly liquid investments, which are readily convertible into cash and have original maturities of three months or less.
	Revenue Recognition - Our operating segments recognize revenue when services are rendered or product is delivered. ONEOK Partners’ natural gas gathering and processing operations record revenue when gas is processed in or transported through its facilities.  ONEOK Partners’ natural gas liquids operations record revenues based upon contracted services and actual volumes exchanged or stored under service agreements in the period services are provided.  Revenue for ONEOK Partners’ natural gas pipelines and a portion of its natural gas liquids operations is recognized based upon contracted capacity and contracted volumes transported and stored under service agreements in the period services are provided.
	Our former Natural Gas Distribution segment’s major industrial and commercial natural gas distribution customers are invoiced at the end of each month.  All natural gas distribution residential customers and some commercial customers are invoiced on a cyclical basis throughout the month, and the utilities accrue unbilled revenues at the end of each month.
	Our revenues from sales to our Energy Services segment’s wholesale customers are accrued in the month of physical delivery based on contracted sales price and estimated volumes.  Demand payments received for requirements contracts are recognized in the period in which the service is provided.  Our fixed-price physical sales are accounted for as derivatives and are recorded at fair value.  See discussion below in “Derivative and Risk Management Activities” for additional information.
	Accounts Receivable - Accounts receivable represent valid claims against nonaffiliated customers for products sold or services rendered, net of allowances for doubtful accounts.  We assess the creditworthiness of our counterparties on an ongoing basis and require security, including prepayments and other forms of collateral, when appropriate.  Outstanding customer receivables are reviewed regularly for possible nonpayment indicators and allowances for doubtful accounts are recorded based upon management’s estimate of collectability at each balance sheet date.  At December 31, 2013 and 2012, our allowance for doubtful accounts was not material.
	Inventories - The values of current natural gas and NGLs in storage are determined using the lower of weighted-average cost or market method.  Noncurrent natural gas and NGLs are classified as property and valued at cost.  Materials and supplies are valued at average cost.
	Commodity Imbalances - Commodity imbalances represent amounts payable or receivable for NGL exchange contracts and natural gas pipeline imbalances and are valued at fair value.  Under the majority of our NGL exchange agreements, we physically receive volumes of unfractionated NGLs, including the risk of loss and legal title to such volumes, from the exchange counterparty.  In turn, we deliver NGL products back to the customer and charge them gathering and fractionation fees. To the extent that the volumes we receive under such agreements differ from those we deliver, we record a net exchange receivable or payable position with the counterparties.  These net exchange receivables and payables are settled with movements of NGL products rather than with cash.  Natural gas pipeline imbalances are settled in cash or in-kind, subject to the terms of the pipelines’ tariffs or by agreement.
	Derivatives and Risk Management Activities - We record all derivative instruments at fair value, with the exception of normal purchases and normal sales that are expected to result in physical delivery.  The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and, if so, the reason for holding it.
	If certain conditions are met, we may elect to designate a derivative instrument as a hedge of exposure to changes in fair values, cash flows or foreign currency.  Certain nontrading derivative transactions, which are economic hedges of our accrual transactions such as our storage and transportation contracts, do not qualify for hedge accounting treatment.
	The table below summarizes the various ways in which we account for our derivative instruments and the impact on our consolidated financial statements:
			Recognition and Measurement
	Accounting Treatment		Balance Sheet		Income Statement
	Normal purchases and	-	Fair value not recorded	-	Change in fair value not recognized in earnings
	normal sales
	Mark-to-market	-	Recorded at fair value	-	Change in fair value recognized in earnings
	Cash flow hedge	-	Recorded at fair value	-	Ineffective portion of the gain or loss on the
					derivative instrument is recognized in earnings
		-	Effective portion of the gain or loss on the	-	Effective portion of the gain or loss on the
			derivative instrument is reported initially as a		derivative instrument is reclassified out of
			component of accumulated other		accumulated other comprehensive income (loss)
			comprehensive income (loss)		into earnings when the forecasted transaction
					affects earnings
	Fair value hedge	-	Recorded at fair value	-	The gain or loss on the derivative instrument is
					recognized in earnings
		-	Change in fair value of the hedged item is	-	Change in fair value of the hedged item is
			recorded as an adjustment to book value		recognized in earnings
	Gains or losses associated with the fair value of derivative instruments entered into by our Natural Gas Distribution segment are included in, and recoverable through, the monthly purchased-gas cost mechanism.
	We formally document all relationships between hedging instruments and hedged items, as well as risk-management objectives, strategies for undertaking various hedge transactions and methods for assessing and testing correlation and hedge ineffectiveness. We specifically identify the asset, liability, firm commitment or forecasted transaction that has been designated as the hedged item.  We assess the effectiveness of hedging relationships quarterly by performing an effectiveness analysis on our cash flow and fair value hedging relationships to determine whether the hedge relationships are highly effective on a retrospective and prospective basis.  We also document our normal purchases and normal sales transactions that we expect to result in physical delivery and that we elect to exempt from derivative accounting treatment.
	The presentation of settled derivative instruments on either a gross or net basis in our Consolidated Statements of Income is dependent on the relevant facts and circumstances of our different types of activities rather than based solely on the terms of the individual contracts.  All financially settled derivative instruments, as well as derivative instruments considered held for trading purposes that result in physical delivery, are reported on a net basis in revenues in our Consolidated Statements of Income.  The realized revenues and purchase costs of derivative instruments that are not considered held for trading purposes and nonderivative contracts are reported on a gross basis.  Derivatives that qualify as normal purchases or normal sales that are expected to result in physical delivery are also reported on a gross basis.
	Revenues in our Consolidated Statements of Income include financial trading margins, as well as certain physical natural gas transactions with our trading counterparties.  Revenues and cost of sales and fuel from such physical transactions are reported on a net basis.
	Cash flows from futures, forwards, options and swaps that are accounted for as hedges are included in the same category as the cash flows from the related hedged items in our Consolidated Statements of Cash Flows.
	See Notes D and E for more discussion of our fair value measurements and risk management and hedging activities using derivatives.
	Property, Plant and Equipment - Our properties are stated at cost, including AFUDC.  Generally, the cost of regulated property retired or sold, plus removal costs, less salvage, is charged to accumulated depreciation.  Gains and losses from sales or retirement of nonregulated properties or an entire operating unit or system of our regulated properties are recognized in income. Maintenance and repairs are charged directly to expense.
	The interest portion of AFUDC represents the cost of borrowed funds used to finance construction activities.  We capitalize interest costs during the construction or upgrade of qualifying assets. Capitalized interest is recorded as a reduction to interest expense. The equity portion of AFUDC represents the capitalization of the estimated average cost of equity used during the construction of major projects and is recorded in the cost of our regulated properties and as a credit to the allowance for equity funds used during construction.
	Our properties are depreciated using the straight-line method over their estimated useful lives.  Generally, we apply composite depreciation rates to functional groups of property having similar economic circumstances.  We periodically conduct depreciation studies to assess the economic lives of our assets.  For our regulated assets, these depreciation studies are completed as a part of our rate proceedings or tariff filings, and the changes in economic lives, if applicable, are implemented prospectively when the new rates are billed.  For our nonregulated assets, if it is determined that the estimated economic life changes, the changes are made prospectively.  Changes in the estimated economic lives of our property, plant and equipment could have a material effect on our financial position or results of operations.
	Property, plant and equipment on our Consolidated Balance Sheets includes construction work in process for capital projects that have not yet been placed in service and therefore are not being depreciated.  Assets are transferred out of construction work in process when they are substantially complete and ready for their intended use.
See Note F for disclosures of our property, plant and equipment.
Impairment of Goodwill and Long-Lived Assets, Including Intangible Assets - We assess our goodwill and indefinite-lived intangible assets for impairment at least annually as of July 1. Our goodwill impairment analysis performed as of July 1, 2013, did not result in an impairment charge nor did our analysis reflect any reporting units at risk, and subsequent to that date, no event has occurred indicating that the implied fair value of each of our reporting units (including its inherent goodwill) is less than the carrying value of its net assets.
As a result of the decline in natural gas prices and its effect on location and seasonal price differentials, we performed an interim impairment assessment of our Energy Services segment’s goodwill balance as of March 31, 2012.  As a result of that assessment, goodwill with a carrying amount of $10.3 million was written down to its implied fair value of zero, with a resulting impairment charge of $10.3 million recorded in 2012 earnings. For the remaining segments, Natural Gas Distribution and ONEOK Partners, there were no impairment indicators as the cash flows generated from each of these segments are derived from predominately fee-based, nondiscretionary services. There were also no impairment charges resulting from our 2012 and 2011 annual impairment tests.
As part of our goodwill impairment test, we first assess qualitative factors (including macroeconomic conditions, industry and market considerations, cost factors and overall financial performance) to determine whether it is more likely than not that the fair value of each of our reporting units is less than its carrying amount. If further testing is necessary, we perform a two-step impairment test for goodwill. In the first step, an initial assessment is made by comparing the fair value of a reporting unit with its book value, including goodwill.  If the fair value is less than the book value, an impairment is indicated, and we must perform a second test to measure the amount of the impairment.  In the second test, we calculate the implied fair value of the goodwill by deducting the fair value of all tangible and intangible net assets of the reporting unit from the fair value determined in step one of the assessment.  If the carrying value of the goodwill exceeds the implied fair value of the goodwill, we will record an impairment charge.
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 multiples to forecasted cash flows.  The multiples used are consistent with historical asset transactions.  The forecasted cash flows are based on average forecasted cash flows over a period of years.
As part of our indefinite-lived intangible asset impairment test, we first assess qualitative factors similar to those considered in the goodwill impairment test to determine whether it is more likely than not that the indefinite-lived intangible asset was impaired. If further testing is necessary, we compare the estimated fair value of our indefinite-lived intangible asset with its book value.  The fair value of our indefinite-lived intangible asset is estimated using the market approach. Under the market approach, we apply multiples to forecasted cash flows of the assets associated with our indefinite-lived intangible asset.  The multiples used are consistent with historical asset transactions.  After assessing qualitative factors, we determined that there were no impairments to our indefinite-lived intangible asset in 2013. There were also no impairment charges resulting from our 2012 and 2011 annual impairment tests.
We assess our long-lived assets, including intangible assets with finite useful lives, 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 determined that there were no asset impairments in 2013, 2012 or 2011.
For the investments we account for under the equity method, the impairment test 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 reevaluate the amount at which we carry our equity method investments to determine whether current events or circumstances warrant adjustments to our carrying value.  We determined that there were no impairments to our investments in unconsolidated affiliates in 2013, 2012 or 2011.
Low natural gas prices and the relatively higher crude oil and NGL prices, compared with natural gas on a heating-value basis, have caused producers primarily to focus development efforts on crude oil and NGL-rich supply basins rather than areas with dry natural gas production, such as the coal-bed methane areas in the Powder River Basin.  The reduced coal-bed methane development activities and natural production declines in the dry natural gas formation of the Powder River Basin resulted in lower volumes available to be gathered.  While the reserve potential in the Powder River Basin still exists, future drilling and development will be affected by commodity prices and producers’ alternative prospects.  Bighorn Gas Gathering, in which ONEOK Partners owns a 49 percent equity interest, has operations in the coal-bed methane areas of the Powder River Basin. Due to declines in volumes gathered on Bighorn Gas Gathering’s system, ONEOK Partners tested its investment for impairment at December 31, 2013. The estimated fair value exceeded the carrying value; however, a decline of 10 percent or more in the fair value of ONEOK Partners’ investment in Bighorn Gas Gathering would result in a noncash impairment charge. ONEOK Partners was not able to estimate reasonably a range of potential future impairment charges, as many of the assumptions that would be used in its estimate of fair value are dependent upon events beyond its control. The carrying amount of ONEOK Partners’ investment as of December 31, 2013, was $87.8 million, which includes $53.4 million in equity method goodwill. ONEOK Partners estimated the fair value of its investment in Bighorn Gas Gathering using an income approach, which discounted the cash flows of ONEOK Partners investment’s underlying assets with a discount rate reflective of its cost of capital and estimated contract rates, volumes, operating and maintenance costs and capital expenditures.
A continued decline in coal-bed methane natural gas volumes in the coal-bed methane production areas of the Powder River Basin may reduce ONEOK Partners’ ability to recover the carrying value of its assets and equity investments in this area and could result in noncash charges to earnings. For ONEOK Partners’ other equity method investments with operations in the Powder River Basin with carrying values of approximately $204 million, which includes approximately $130 million in equity method goodwill, ONEOK Partners did not identify current events or circumstances that warranted an impairment analysis or an adjustment to its carrying values. ONEOK Partners is not able to reasonably estimate a range of potential future charges, as many of the assumptions that would be used in a fair value model are dependent upon events such as commodity prices, producers’ drilling and production activity and effects of government regulations and policies.
Our impairment tests require the use of assumptions and estimates such as industry economic factors and the profitability of future business strategies.  If actual results are not consistent with our assumptions and estimates or our assumptions and estimates change due to new information, we may be exposed to future impairment charges.
See Notes F, G and P for our long-lived assets, goodwill and intangible assets and investment in unconsolidated affiliates disclosures.
Regulation - Our former natural gas distribution operations and ONEOK Partners’ intrastate natural gas transmission pipelines are subject to the rate regulation and accounting requirements of the OCC, KCC, RRC and various municipalities in Texas. ONEOK Partners’ interstate natural gas and natural gas liquids pipelines are subject to regulation by the FERC.  In Kansas and Texas, natural gas storage may be regulated by the state and the FERC for certain types of services.  Oklahoma Natural Gas, Kansas Gas Service, Texas Gas Service and portions of our ONEOK Partners segment follow the accounting and reporting guidance for regulated operations.  During the rate-making process, regulatory authorities set the framework for what we can charge customers for our services and establish the manner that our costs are accounted for, including allowing us to defer recognition of certain costs and permitting recovery of the amounts through rates over time, as opposed to expensing such costs as incurred. Examples include costs for fuel and fuel losses, acquisition costs and contributions in aid of construction. This allows us to stabilize rates over time rather than passing such costs on to the customer for immediate recovery.  Actions by regulatory authorities could have an effect on the amount recovered from rate payers.  Any difference in the amount recoverable and the amount deferred is recorded as income or expense at the time of the regulatory action.  A write-off of regulatory assets and costs not recovered may be required if all or a portion of the regulated operations have rates that are no longer:
•	established by independent, third-party regulators;
•	designed to recover the specific entity’s costs of providing regulated services; and
•	set at levels that will recover our costs when considering the demand and competition for our services.
In December 2013, the KCC approved a settlement agreement for the separation of our Kansas Gas Service natural gas distribution business to ONE Gas from ONEOK. The terms of the settlement agreement provided that amounts previously recorded as a regulatory asset related to ONEOK’s acquisition of Kansas Gas Service in 1997 would no longer be recovered in rates. As a result, the carrying amount of the regulatory asset was written off, and we recorded a noncash charge to income of approximately $10.2 million in the fourth quarter 2013.
At December 31, 2013 and 2012, we recorded regulatory assets of approximately $383.6 million and $585.0 million, respectively, which are being recovered or are expected to be recovered as a result of various approved rate proceedings.  Of these amounts, the total regulatory assets related to our natural gas distribution business were $376.8 million and $577.1 million at December 31, 2013 and 2012, respectively. The natural gas distribution balances included approximately $341.1 million and $499.4 million related to our pension and postretirement benefit plans at December 31, 2013 and 2012, respectively, which are discussed in Note N.  Regulatory assets are being recovered as a result of approved rate proceedings over varying time periods up to 25 years.  These assets are reflected in other assets on our Consolidated Balance Sheets.
Pension and Postretirement Employee Benefits - We have defined benefit retirement plans covering certain full-time employees. We sponsor welfare plans that provide postretirement medical and life insurance benefits to certain employees who retire with at least five years of service.  Our actuarial consultant calculates the expense and liability related to these plans and uses statistical and other factors that attempt to anticipate future events.  These factors include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, age and employment periods.  In determining the projected benefit obligations and costs, assumptions can change from period to period and may result in material changes in the costs and liabilities we recognize.  See Note N for more discussion of pension and postretirement employee benefits.
Income Taxes - Deferred income taxes are recorded for the difference between the financial statement and income tax basis of assets and liabilities and carryforward items, based on income tax laws and rates existing at the time the temporary differences are expected to reverse.  The effect on deferred taxes of a change in tax rates is deferred and amortized for operations regulated by the OCC, KCC, RRC and various municipalities in Texas, if, as a result of an action by a regulator, it is probable that the effect of the change in tax rates will be recovered from or returned to customers through future rates.  For all other operations, the effect is recognized in income in the period that includes the enactment date.  We continue to amortize previously deferred investment tax credits for ratemaking purposes over the period prescribed by the OCC, KCC, RRC and various municipalities in Texas.
We utilize a more-likely-than-not recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position that is taken or expected to be taken in a tax return.  We reflect penalties and interest as part of income tax expense as they become applicable for tax provisions that do not meet the more-likely-than-not recognition threshold and measurement attribute.  During 2013, 2012 and 2011, our tax positions did not require an establishment of a material reserve.
We file numerous consolidated and separate income tax returns with federal tax authorities of the United States and Canada, along with the tax authorities of several states.  There are no United States federal audits or statute waivers at this time. See Note O for additional discussion of income taxes.
Asset Retirement Obligations - Asset retirement obligations represent legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development and/or normal use of the asset.  Certain long-lived assets that comprise our natural gas distribution systems and ONEOK Partners’ natural gas gathering and processing, natural gas liquids and pipeline facilities are subject to agreements or regulations that give rise to an asset retirement obligation for removal or other disposition costs associated with retiring the assets in place upon the discontinued use of the assets. We recognize the fair value of a liability for an asset-retirement obligation in the period when it is incurred if a reasonable estimate of the fair value can be made.  We are not able to estimate reasonably the fair value of the asset retirement obligations for portions of our and ONEOK Partners’ assets because the settlement dates are indeterminable given the expected continued use of the assets with proper maintenance. We expect our former natural gas distribution assets and ONEOK Partners’ pipeline assets, for which we are unable to estimate reasonably the fair value of the asset retirement obligation, will continue to operate as long as natural gas supply and demand for natural gas and natural gas liquids exists. Based on the widespread use of natural gas for heating and cooking activities by residential users and electric-power generation by commercial users, as well as use of natural gas liquids by the petrochemical industry, we and ONEOK Partners expect supply and demand to exist for the foreseeable future.
For our assets where we are able to make an estimate, the fair value of the liability is added to the carrying amount of the associated asset, and this additional carrying amount is depreciated over the life of the asset.  The liability is accreted at the end of each period through charges to operating expense.  If the obligation is settled for an amount other than the carrying amount of the liability, we will recognize a gain or loss on settlement.  The depreciation and accretion expense are immaterial to our consolidated financial statements.
In accordance with long-standing regulatory treatment, we collect, through rates, the estimated costs of removal on certain regulated properties through depreciation expense, with a corresponding credit to accumulated depreciation and amortization. These removal costs collected through our rates include costs attributable to legal and nonlegal removal obligations; however, the amounts collected that are in excess of these nonlegal asset-removal costs incurred are accounted for as a regulatory liability for financial reporting purposes. Historically, with the exception of the regulatory authority in Kansas, the regulatory authorities that have jurisdiction over our regulated operations have not required us to quantify or disclose this amount; rather, these costs are addressed prospectively in depreciation rates and are set in each general rate order. We have made an estimate of our regulatory liability using current rates since the last general rate order in each of our jurisdictions; however, for financial reporting purposes, significant uncertainty exists regarding the future disposition of this regulatory liability, pending, among other issues, clarification of regulatory intent.  We continue to monitor the regulatory requirements, and the liability may be adjusted as more information is obtained.  We record the estimated asset removal obligation in noncurrent liabilities in other deferred credits on our Consolidated Balance Sheets.  To the extent this estimated liability is adjusted, such amounts will be reclassified between accumulated depreciation and amortization and other deferred credits and therefore will not have an impact on earnings.
Contingencies - Our accounting for contingencies covers a variety of business activities, including contingencies for legal and environmental exposures.  We accrue these contingencies when our assessments indicate that it is probable that a liability has been incurred or an asset will not be recovered and an amount can be estimated reasonably.  We expense legal fees as incurred and base our legal liability estimates on currently available facts and our estimates of the ultimate outcome or resolution. Accruals for estimated losses from environmental remediation obligations generally are recognized no later than the completion of a remediation feasibility study.  Recoveries of environmental remediation costs from other parties are recorded as assets when their receipt is deemed probable.  Actual results may differ from our estimates resulting in an impact, positive or negative, on earnings.  See Note R for additional discussion of contingencies.
Share-Based Payments - We expense the fair value of share-based payments net of estimated forfeitures.  We estimate forfeiture rates based on historical forfeitures under our share-based payment plans.
Earnings per Common Share - Basic EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period.  Diluted EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period plus potentially dilutive components.  The dilutive components are calculated based on the dilutive effect for each quarter.  For fiscal-year periods, the dilutive components for each quarter are averaged to arrive at the fiscal year-to-date dilutive component.
Recently Issued Accounting Standards Update - In July 2013, the FASB issued ASU 2013-10, “Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes,” which allows an entity to designate the Fed Funds Effective Swap rate (also known as the Overnight Index Swap rate, or OIS rate, in the United States) as a benchmark interest rate for hedge accounting purposes in addition to the interest rates on direct Treasury obligations of the United States government and LIBOR. In addition, this guidance removes the restriction on using different benchmark interest rates for similar hedges. This guidance was effective prospectively for qualifying new or redesignated hedging relationships entered into on or after July 17, 2013. We adopted this guidance with our September 30, 2013, Quarterly Report, and it did not impact materially our financial position or results of operations. See Note E for additional disclosures.
In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income,” which requires presentation in a single location, either in a single note or parenthetically on the face of the financial statements, the effect of significant amounts reclassified from each component of accumulated other comprehensive income based on its source.  We adopted this guidance with our March 31, 2013, Quarterly Report, and it did not impact our financial position or results of operations. See Note K for additional disclosures.
In July 2012, the FASB issued ASU 2012-02, “Testing Indefinite-lived Intangible Assets for Impairment,” which allows companies to perform a “qualitative” assessment to determine whether further impairment testing of indefinite-lived intangible assets is necessary.  Under the revised standard, an entity is not required to calculate the fair value of an indefinite-lived intangible asset and perform the quantitative impairment test unless the entity determines that it is more likely than not that the asset is impaired.  An entity has the option to bypass the qualitative assessment and perform the quantitative impairment test for any indefinite-lived intangible assets in any period.  We adopted this guidance for our annual assessments beginning in July 2013, and it did not impact our financial position or results of operations.
In December 2011, the FASB issued ASU No. 2011-11, “Disclosures about Offsetting Assets and Liabilities,” which increases disclosures about offsetting assets and liabilities. In January 2013, the FASB issued ASU 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities,” which clarifies that the scope of ASU 2011-11 applies to derivatives accounted for in accordance with Topic 815, Derivatives and Hedging. New disclosures are required to enable users of financial statements to understand significant quantitative differences in balance sheets prepared under GAAP and International Financial Reporting Standards related to the offsetting of financial instruments, including derivatives. The existing GAAP guidance allowing balance sheet offsetting remains unchanged. This guidance was effective for interim and annual periods beginning on January 1, 2013, and was applied retrospectively for all comparative periods presented. The adoption of this guidance beginning with our March 31, 2013, Quarterly Report did not affect our financial condition, results of operations or cash flows.

EXIT_ACTIVITIES_Notes

EXIT ACTIVITIES (Notes)	12 Months Ended
	Dec. 31, 2013
EXIT ACTIVITIES [Abstract]	'
Restructuring and Related Activities Disclosure [Text Block]	'
	B.	EXIT ACTIVITIES
	Wind down of Energy Services Business - In June 2013, we announced we would exit the operations of our Energy Services segment through an accelerated wind down process. Our Energy Services segment has faced challenging industry conditions that show no signs of improving. Increased natural gas supply and infrastructure, coupled with lower natural gas price volatility and narrowed seasonal and location natural gas price differentials, has resulted in limited opportunities to generate revenues to cover our fixed costs on our contracted storage and transportation capacity. We executed agreements in 2013 to release a significant portion of our nonaffiliated natural gas transportation and storage contracts to third parties between July 1 and December 31, 2013, at current market rates that resulted in noncash charges of $138.6 million. In addition, pursuant to a request for proposal, our Energy Services segment assigned contracts for 18.0 Bcf of affiliated storage capacity to our Natural Gas Distribution segment in June 2013. Our Energy Services segment will continue to serve its existing contracted premium-services customers during the wind down, and we expect the Energy Services segment to be classified as discontinued operations, effective April 1, 2014, when substantially all operations of the segment have ceased.
	The following table summarizes the change in our liability related to released capacity contracts for the period indicated:
		Year Ended
		31-Dec-13
		(Millions of dollars)
	Beginning balance	$	—
	Noncash charges	138.6
	Settlements	(17.7		)
	Accretion	1.1
	Ending balance	$	122
	We recorded these noncash charges in cost of sales and fuel in our Consolidated Statements of Income. We expect to record an additional noncash charge of approximately $1.7 million before taxes in the first quarter 2014, to reflect the assignment of our remaining natural gas storage contract that extends beyond March 31, 2014. We do not expect the total charge attributable to any severance benefits will be material. We expect future cash payments associated with released transportation and storage capacity from the wind down of our Energy Services segment to total approximately $80 million on an after-tax basis, which consist of approximately $33 million paid in 2014, $24 million in 2015, $13 million in 2016, and $10 million during the period from 2017 through 2023.

DISCONTINUED_OPERATIONS

DISCONTINUED OPERATIONS	12 Months Ended
	Dec. 31, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
DISCONTINUED OPERATIONS	'
	C.	DISCONTINUED OPERATIONS
	On February 1, 2012, we sold ONEOK Energy Marketing Company, our Natural Gas Distribution segment’s retail natural gas marketing business, to Constellation Energy Group, Inc. for $22.5 million plus working capital.  We received net proceeds of approximately $32.9 million and recognized a gain on the sale of approximately $13.5 million, net of taxes of $8.3 million. The proceeds from the sale were used to reduce short-term borrowings.  The financial information of ONEOK Energy Marketing Company is reflected as discontinued operations in this Annual Report.  All prior periods presented have been recast to reflect the discontinued operations.
	The amounts of revenue, costs and income taxes reported in discontinued operations are set forth in the table below for the periods indicated:
			One Month Ended			Year Ended
			January 31,			December 31,
			2012			2011
			(Thousands of dollars)
	Revenues		$	27,607		$	313,371
	Cost of sales and fuel		25,961			302,561
	Net margin		1,646			10,810
	Operating costs		408			7,147
	Depreciation and amortization		8			128
	Operating income		1,230			3,535
	Other income (expense), net		—			(50		)
	Income taxes		(468		)	(1,255		)
	Income from discontinued operations, net		$	762		$	2,230
	Separation of Natural Gas Distribution Business - On January 31, 2014, we completed the separation of our natural gas distribution business into a standalone publicly traded company, ONE Gas.  ONE Gas consists of ONEOK’s former Natural Gas Distribution segment that includes Kansas Gas Service, Oklahoma Natural Gas and Texas Gas Service.  The Natural Gas Distribution segment was classified as discontinued operations, effective February 1, 2014. See additional discussion in Note U of the Notes to the Consolidated Financial Statements.

FAIR_VALUE_MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
FAIR VALUE MEASUREMENTS	'
	D.	FAIR VALUE MEASUREMENTS
	Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements for the periods indicated:
			December 31, 2013
			Level 1			Level 2			Level 3			Total - Gross			Netting			Total - Net
			(Thousands of dollars)
	Assets
	Derivatives (a)
	Commodity contracts
	Financial contracts		$	4,477		$	647		$	3,094		$	8,218		$	(2,850	)	$	5,368
	Physical contracts		—			4			1,764			1,768			(1,157		)	611
	Interest-rate contracts		—			54,503			—			54,503			—			54,503
	Total derivative assets		4,477			55,154			4,858			64,489			(4,007		)	60,482
	Fair value of firm commitments (b)		—			—			599			599			—			599
	Available-for-sale investment securities (b)		1,569			—			—			1,569			—			1,569
	Total assets		$	6,046		$	55,154		$	5,457		$	66,657		$	(4,007	)	$	62,650
	Liabilities
	Derivatives (a)
	Commodity contracts
	Financial contracts		$	(7,624	)	$	(776	)	$	(3,435	)	$	(11,835	)	$	10,767		$	(1,068	)
	Physical contracts		—			(4		)	(4,117		)	(4,121		)	1,157			(2,964		)
	Total derivative liabilities		$	(7,624	)	$	(780	)	$	(7,552	)	$	(15,956	)	$	11,924		$	(4,032	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets as energy marketing and risk management assets and liabilities, other assets and other deferred credits on a net basis. We net derivative assets and liabilities, including cash collateral, when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2013, we held no cash collateral and had posted $15.7 million of cash collateral with various counterparties.
	(b) - Included in our Consolidated Balance Sheets as other assets.
			December 31, 2012
			Level 1			Level 2			Level 3			Total - Gross			Netting			Total - Net
			(Thousands of dollars)
	Assets
	Derivatives (a)
	Commodity contracts
	Financial contracts		$	69,957		$	10,780		$	7,107		$	87,844		$	(51,602	)	$	36,242
	Physical contracts		—			2,083			2,032			4,115			(151		)	3,964
	Interest-rate contracts		—			10,923			—			10,923			—			10,923
	Total derivative assets		69,957			23,786			9,139			102,882			(51,753		)	51,129
	Trading securities (b)		5,978			—			—			5,978			—			5,978
	Available-for-sale investment securities (c)		2,027			—			—			2,027			—			2,027
	Total assets		$	77,962		$	23,786		$	9,139		$	110,887		$	(51,753	)	$	59,134
	Liabilities
	Derivatives (a)
	Commodity contracts
	Financial contracts		$	(35,172	)	$	(1,737	)	$	(7,177	)	$	(44,086	)	$	33,878		$	(10,208	)
	Physical contracts		—			—			(279		)	(279		)	151			(128		)
	Total derivative liabilities		(35,172		)	(1,737		)	(7,456		)	(44,365		)	34,029			(10,336		)
	Fair value of firm commitments (d)		—			—			(1,280		)	(1,280		)	—			(1,280		)
	Total liabilities		$	(35,172	)	$	(1,737	)	$	(8,736	)	$	(45,645	)	$	34,029		$	(11,616	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets as energy marketing and risk management assets and liabilities, other assets and other deferred credits on a net basis. We net derivative assets and liabilities, including cash collateral, when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2012, we held $17.7 million of cash collateral and had posted $4.5 million of cash collateral with various counterparties.
	(b) - Included in our Consolidated Balance Sheets as other current assets.
	(c) - Included in our Consolidated Balance Sheets as other assets.
	(d) - Included in our Consolidated Balance Sheets as other current liabilities and other deferred credits.
	Our Level 1 fair value amounts are based on unadjusted quoted prices in active markets including NYMEX-settled prices and actively quoted prices for equity securities. These balances are comprised predominantly of exchange-traded derivative contracts for natural gas and crude oil. Also included in Level 1 are equity securities.
	Our Level 2 fair value amounts are based on significant observable pricing inputs, such as NYMEX-settled prices for natural gas and crude oil, and financial models that utilize implied forward LIBOR yield curves for interest-rate swaps.
	Our Level 3 fair value amounts are based on inputs that may include one or more unobservable inputs including internally developed basis curves that incorporate observable and unobservable market data, NGL price curves from broker quotes, market volatilities derived from the most recent NYMEX close spot prices and forward LIBOR curves, and adjustments for the credit risk of our counterparties.  We corroborate the data on which our fair value estimates are based using our market knowledge of recent transactions, analysis of historical correlations and validation with independent broker quotes.  These balances categorized as Level 3 are comprised of derivatives for natural gas and NGLs.  Also included in Level 3 are the fair values of firm commitments.  We do not believe that our Level 3 fair value estimates have a material impact on our results of operations, as the majority of our derivatives are accounted for as hedges for which ineffectiveness is not material.  The significant unobservable inputs used are the unpublished forward basis and index curves.  Significant increases or decreases in either of those inputs in isolation would not have a material impact on our fair value measurements.
	The following tables set forth the reconciliation of our Level 3 fair value measurements for the periods indicated:
			Derivative			Fair Value of			Total
			Assets			Firm
			(Liabilities)			Commitments
			(Thousands of dollars)
	1-Jan-13		$	1,683		$	(1,280	)	$	403
	Total realized/unrealized gains (losses):
	Included in earnings (a)		(5,627		)	1,879			(3,748		)
	Included in other comprehensive income (loss)		800			—			800
	Settlements		450			—			450
	31-Dec-13		$	(2,694	)	$	599		$	(2,095	)
	Total gains (losses) for the period included in earnings attributable to the change in		$	(804	)	$	670		$	(134	)
unrealized gains (losses) relating to assets and liabilities still held as of
December 31, 2013 (a)
(a) - Reported in revenues and cost of sales and fuel in our Consolidated Statements of Income.
		Derivative			Fair Value of			Total
		Assets			Firm
		(Liabilities)			Commitments
		(Thousands of dollars)
1-Jan-12		$	25,104		$	(7,283	)	$	17,821
Total realized/unrealized gains (losses):
Included in earnings (a)		(13,503		)	6,003			(7,500		)
Included in other comprehensive income (loss)		(5,587		)	—			(5,587		)
Sale of discontinued operations		(3,636		)	—			(3,636		)
Transfers out of Level 3		(695		)	—			(695		)
31-Dec-12		$	1,683		$	(1,280	)	$	403
Total gains (losses) for the period included in earnings attributable to the change in		$	1,971		$	(112	)	$	1,859
unrealized gains (losses) relating to assets and liabilities still held as of
December 31, 2012 (a)
(a) - Reported in revenues and cost of sales and fuel in our Consolidated Statements of Income.
Realized/unrealized gains (losses) include the realization of our derivative contracts through maturity and changes in fair value of our hedged firm commitments. We recognize transfers into and out of the levels in the fair value hierarchy as of the end of each reporting period.  We had no transfers into or out of Level 1 during the periods presented.  Transfers into Level 3 represent existing assets or liabilities that were previously categorized at a higher level for which the unobservable inputs became a more significant portion of the fair value estimates.  Transfers out of Level 3 represent existing assets and liabilities that were classified previously as Level 3 for which the observable inputs became a more significant portion of the fair value estimates.
Our Level 3 fair value measurements based on unobservable inputs, excluding the portion of our fair value measurements based on third-party pricing information without adjustment, are not material at December 31, 2013.
Other Financial Instruments - The approximate fair value of cash and cash equivalents, accounts receivable, accounts payable and notes payable is equal to book value, due to the short-term nature of these items. Our cash and cash equivalents are comprised of bank and money market accounts and are classified as Level 1.  Our notes payable are classified as Level 2 since the estimated fair value of the notes payable 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 $8.2 billion and $7.5 billion at December 31, 2013 and 2012, respectively.  The book value of long-term debt, including current maturities, was $7.8 billion and $6.5 billion at December 31, 2013 and 2012, respectively.  The estimated fair value of the aggregate of ONEOK’s and ONEOK Partners’ senior notes 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.

RISK_MANAGEMENT_AND_HEDGING_AC

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES	'
	E.	RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES
	Our Energy Services and ONEOK Partners segments are exposed to various risks that we manage by periodically entering into derivative instruments. In June 2013, we announced we will exit the operations of our Energy Services segment. As a result, the use of derivative instruments will decrease significantly within our Energy Services segment. See Note C for additional information. These risks include the following:
	•	Commodity-price risk - We are exposed 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 use commodity derivative instruments such as futures, physical-forward contracts, swaps and options to mitigate the commodity-price risk associated with a portion of the forecasted purchases and sales of commodities and natural gas and natural gas liquids in storage.  Commodity-price volatility may have a significant impact on the fair value of our derivative instruments as of a given date;
	•	Basis risk - We are exposed to the risk of loss in cash flows and future earnings arising from adverse changes in the location price differentials between pipeline receipt and delivery locations.  Our firm transportation capacity allows us to purchase natural gas at a pipeline receipt point and sell natural gas at a pipeline delivery point.  As market conditions permit, our Energy Services segment periodically enters into basis swaps between the transportation receipt and delivery points in order to protect the fair value of these location price differentials related to our firm commitments; and
	•	Interest-rate risk - We are also subject to fluctuations in interest rates.  We manage interest-rate risk through the use of fixed-rate debt, floating-rate debt and, at times, interest-rate swaps.
	The following derivative instruments are used to manage our exposure to these risks:
	•	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. This transfers 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.
	Our objectives for entering into such contracts include but are not limited to:
	•	reducing the variability of cash flows by locking in the price for all or a portion of anticipated index-based physical purchases and sales, transportation fuel requirements, asset management transactions and customer-related business activities;
	•	locking in a location price differential to protect the fair value between transportation receipt and delivery points and to protect the fair value of natural gas or NGLs that are purchased in one month and sold in a later month;
	•	reducing our exposure to fluctuations in interest rates; and
	•	reducing variability in cash flows from changes in interest rates associated with forecasted debt issuances.
	With respect to the net open positions that exist within our marketing operations, fluctuating commodity prices can impact our financial position and results of operations.  The net open positions are managed actively, and the impact of the changing prices on our financial condition at a point in time is not necessarily indicative of the impact of price movements throughout the year.
	Our former Natural Gas Distribution segment also used derivative instruments to hedge the cost of a portion of anticipated natural gas purchases during the winter heating months to protect our customers from upward volatility in the market price of natural gas. The use of these derivative instruments and the associated recovery of these costs have been approved by the OCC, KCC and regulatory authorities in certain Texas jurisdictions.
	ONEOK Partners has forward-starting interest-rate swaps designated as cash flow hedges of the variability of interest payments on a portion of forecasted debt issuances that may result from changes in the benchmark interest rate before the debt is issued.  At December 31, 2013 and 2012, ONEOK Partners had forward-starting interest-rate swaps with notional amounts totaling $400 million. In February 2014, ONEOK Partners entered into forward-starting interest-rate swaps with notional amounts totaling $500 million with settlement dates less than 12 months that were designated as cash flow hedges.
	Fair Values of Derivative Instruments - The following table sets forth the fair values of our derivative instruments for our continuing and discontinued operations for the periods indicated:
		December 31, 2013									December 31, 2012
		Fair Values of Derivatives (a)									Fair Values of Derivatives (a)
		Assets					(Liabilities)				Assets					(Liabilities)
		(Thousands of dollars)
	Derivatives designated as hedging instruments
	Commodity contracts
	Financial contracts	$	8,011		(b)		$	(10,573	)		$	47,516		(c)		$	(4,885	)
	Physical contracts	1,064					(3,463		)		56					(126		)
	Interest-rate contracts	54,503					—				10,923					—
	Total derivatives designated as hedging instruments	63,578					(14,036		)		58,495					(5,011		)
	Derivatives not designated as hedging instruments
	Commodity contracts
	Nontrading instruments
	Financial contracts	202					(1,262		)		24,970					(25,009		)
	Physical contracts	704					(658		)		4,059					(153		)
	Trading instruments
	Financial contracts	5					—				15,358					(14,192		)
	Total derivatives not designated as hedging instruments	911					(1,920		)		44,387					(39,354		)
	Total derivatives	$	64,489				$	(15,956	)		$	102,882				$	(44,365	)
	(a) - Included on a net basis in energy marketing and risk-management assets and liabilities or other assets on our Consolidated Balance Sheets.
	(b) - Includes $5.8 million of derivative assets associated with cash flow hedges of inventory that were adjusted to reflect the lower of cost or market value. The deferred gains associated with these assets have been reclassified from accumulated other comprehensive income (loss).
	(c) - Includes $16.9 million of derivative net assets and ineffectiveness associated with cash flow hedges of inventory related to certain financial contracts that were used to hedge forecasted purchases and sales of natural gas. The deferred gains associated with these assets have been reclassified from accumulated other comprehensive income (loss).
	Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for derivative instruments held for our continuing and discontinued operations for the periods indicated:
				December 31, 2013							December 31, 2012
		Contract		Purchased/				Sold/			Purchased/				Sold/
		Type		Payor				Receiver			Payor				Receiver
	Derivatives designated as hedging instruments:
	Cash flow hedges
	Fixed price
	-Natural gas (Bcf)	Futures, forwards and swaps		—				(65.0	)		—				(85.1	)
	-Crude oil and NGLs (MMBbl)	Futures, forwards and swaps		—				(4.0	)		—				(1.1	)
	Basis
	-Natural gas (Bcf)	Futures, forwards and swaps		—				(57.4	)		—				(56.3	)
	Interest-rate contracts (Millions of dollars)	Forward-starting		$	400			—			$	400			—
		swaps
	Fair value hedges
	Basis
	-Natural gas (Bcf)	Futures, forwards and swaps		1.1				(1.1	)		59.1				(59.1	)
	Derivatives not designated as hedging instruments:
	Fixed price
	-Natural gas (Bcf)	Futures, forwards and swaps		5.8				(9.7	)		60.7				(60.4	)
		Options		—				—			102.1				(100.8	)
	-Crude oil and NGLs (MMBbl)	Futures, forwards and swaps		0.3				(0.3	)		—				—
	Basis
-Natural gas (Bcf)	Futures, forwards and swaps		8.5				(11.2	)		80.2				(81.7	)
Index
-Natural gas (Bcf)	Futures, forwards and swaps		1.8				—			20.3				(22.3	)
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 - Our Energy Services and ONEOK Partners segments use derivative instruments to hedge the cash flows associated with anticipated purchases and sales of natural gas, NGLs and condensate and cost of fuel used in the transportation of natural gas.  Accumulated other comprehensive income (loss) at December 31, 2013, includes losses of approximately $5.8 million, net of tax, related to these hedges that will be recognized within the next 24 months as the forecasted transactions affect earnings.  If prices remain at current levels, we will recognize $7.0 million in net losses over the next 12 months and net gains of $1.2 million thereafter.  The amount deferred in accumulated other comprehensive income (loss) attributable to our settled interest-rate swaps is a loss of $49.6 million, net of tax, which will be recognized over the life of the long-term, fixed-rate debt. We expect that losses of $5.3 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 income (loss) are attributable primarily to ONEOK Partners’ forward-starting interest-rate swaps with settlement dates greater than 12 months, which will be amortized to interest expense over the life of long-term, fixed-rate debt upon issuance of ONEOK Partners debt.
For the year ended December 31, 2013, cost of sales and fuel in our Consolidated Statements of Income includes $10.1 million reflecting an adjustment to natural gas inventory at the lower of cost or market value. We reclassified $8.0 million of deferred gains, before income taxes, on associated cash flow hedges from accumulated other comprehensive income (loss) into earnings. For the year ended December 31, 2012, net margin in our Consolidated Statement of Income included losses of $29.9 million related to certain financial contracts that were used to hedge forecasted purchases of natural gas.  As a result of the continued decline in natural gas prices, the combination of the cost basis of the forecasted purchases of inventory and the financial contracts exceeded the amount expected to be recovered through sales of that inventory after considering related sales hedges, which required reclassification of the loss from accumulated other comprehensive loss to current period earnings. In 2011, cost of sales and fuel in our Consolidated Statements of Income included $91.1 million, reflecting an adjustment to natural gas inventory at the lower of cost or market value.  We also reclassified $91.1 million of deferred gains, before income taxes, on associated cash flow hedges from accumulated other comprehensive income (loss) into earnings.
The following table sets forth the effect of cash flow hedges recognized in other comprehensive income (loss) for the periods indicated:
Derivatives in Cash Flow		Years Ended December 31,
Hedging Relationships		2013				2012				2011
		(Thousands of dollars)
Commodity contracts		$	(15,433	)		$	62,898			$	117,508
Interest-rate contracts		46,616				(29,471		)		(128,666		)
Total gain (loss) recognized in other comprehensive income (loss) on derivatives		$	31,183			$	33,427			$	(11,158	)
(effective portion)
The following tables set forth the effect of cash flow hedges on our Consolidated Statements of Income for the periods indicated:
		Location of Gain (Loss) Reclassified from
Derivatives in Cash Flow		Accumulated Other Comprehensive Income		Years Ended December 31,
Hedging Relationships		(Loss) into Net Income (Effective Portion)		2013				2012				2011
				(Thousands of dollars)
Commodity contracts		Revenues		$	19,049			$	140,862			$	48,601
Commodity contracts		Cost of sales and fuel		(14,320		)		(73,881		)		89,618
Interest-rate contracts		Interest expense		(14,560		)		(7,155		)		(480		)
Total gain (loss) reclassified from accumulated other comprehensive income				$	(9,831	)		$	59,826			$	137,739
(loss) into net income on derivatives (effective portion)
Ineffectiveness related to our cash flow hedges was not material for the years ended December 31, 2013, 2012 and 2011.  In the event that it becomes probable that a forecasted transaction will not occur, we will discontinue cash flow hedge treatment, which will affect earnings.  For the year ended December 31, 2013, we recorded immaterial gains due to the discontinuance of cash flow hedge treatment as a result of the underlying transactions being no longer probable. For the years ended December 31, 2012 and 2011, there were no gains or losses due to the discontinuance of cash flow hedge treatment as a result of the underlying transactions being no longer probable.
Other Derivative Instruments - The following table sets forth the effect of our derivative instruments that are not part of a hedging relationship on our Consolidated Statements of Income for our continuing and discontinued operations for the periods indicated:
Derivatives Not Designated as		Location of Gain (Loss)		Years Ended December 31,
Hedging Instruments				2013				2012				2011
				(Thousands of dollars)
Commodity contracts - trading		Revenues		$	(2,051	)		$	2,413			$	1,796
Commodity contracts - non-trading (a)		Cost of sales and fuel		(2,266		)	(b)	5,956				16,178
Total gain (loss) recognized in income on derivatives				$	(4,317	)		$	8,369			$	17,974
(a) - Amounts are presented net of deferred losses associated with derivatives entered into by our Natural Gas Distribution segment.
(b) - Includes losses of $2.2 million for the year ended December 31, 2013, on certain derivatives derecognized that were designated previously as fair value hedges of firm transportation commitments that no longer meet the definition of a firm commitment.
Our former Natural Gas Distribution segment held natural gas call options with fair values of $8.7 million and $1.8 million at December 31, 2013 and 2012, respectively.  The premiums are recorded in other current assets as these contracts are included in, and recoverable through, the monthly purchased-gas cost mechanism.  We recorded losses of $4.5 million, $5.9 million and $14.5 million for the years ended December 31, 2013, 2012 and 2011, respectively, which are deferred as part of our unrecovered purchased-gas costs.
Fair Value Hedges - In prior years, we terminated various interest-rate swap agreements that had been designated as fair value hedges. The net savings from the termination of these swaps is being recognized in interest expense over the terms of the debt instruments originally hedged.  Interest expense savings from the amortization of terminated swaps for 2013, 2012 and 2011, were $1.7 million, $1.7 million and $4.3 million, respectively.
Our Energy Services segment uses basis swaps to hedge the fair value of location price differentials related to certain firm transportation commitments.  Cost of sales and fuel in our Consolidated Statements of Income includes losses of $1.4 million, and gains of $0.4 million and $14.6 million for the years ended December 31, 2013, 2012 and 2011, respectively, related to the change in fair value of derivatives designated as fair value hedges.  Revenues include gains of $1.6 million and $0.5 million, and losses of $13.8 million for the years ended December 31, 2013, 2012 and 2011, respectively, to recognize the change in fair value of the related hedged firm commitments.  The ineffectiveness related to these hedges was not material for the years ended December 31, 2013, 2012 and 2011.
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 have counterparties whose credit is not rated, and for those customers we use internally developed credit ratings.
Some of our derivative instruments contain provisions that require us to maintain an investment-grade credit rating from S&P and/or Moody’s.  If our credit ratings on 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. The aggregate fair value of all financial derivative instruments with contingent features related to credit risk that were in a net liability position as of December 31, 2013, was $1.1 million.  On February 3, 2014, S&P reduced our credit rating below investment grade as a result of the ONE Gas separation. Moody’s also downgraded our credit rating; however, our credit rating with Moody’s remained investment-grade.
The counterparties to our derivative contracts consist primarily of major energy companies, LDCs, electric utilities, financial institutions and commercial and industrial end-users.  This concentration of counterparties may impact our overall exposure to credit risk, either positively or negatively, in that the counterparties may be similarly affected 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 December 31, 2013, the net credit exposure from our derivative assets is primarily with investment-grade companies in the financial services sector.

PROPERTY_PLANT_AND_EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Abstract]	'
PROPERTY, PLANT AND EQUIPMENT	'
	F.	PROPERTY, PLANT AND EQUIPMENT
	The following table sets forth our property, plant and equipment by property type, for the periods indicated:
			Estimated Useful	December 31,			December 31,
			Lives (Years)	2013			2012
				(Thousands of dollars)
	Non-Regulated
	Gathering pipelines and related equipment		5 to 40	$	2,173,271		$	1,638,037
	Processing and fractionation and related equipment		5 to 40	2,295,983			1,625,146
	Storage and related equipment		5 to 54	362,704			335,237
	Transmission pipelines and related equipment		22 to 54	302,718			311,038
	General plant and other		2 to 60	402,523			348,636
	Construction work in process		—	1,112,182			881,788
	Regulated
	Natural gas distribution pipelines and related equipment		15 to 80	3,703,593			3,512,660
	Storage and related equipment		5 to 54	135,922			136,938
	Natural gas transmission pipelines and related equipment		5 to 77	1,850,559			1,796,683
	Natural gas liquids transmission pipelines and related equipment		5 to 80	2,049,461			1,490,511
	General plant and other		2 to 85	324,703			309,119
	Construction work in process		—	822,537			703,198
	Property, plant and equipment			15,536,156			13,088,991
	Accumulated depreciation and amortization - non-regulated			(1,112,192		)	(954,398		)
	Accumulated depreciation and amortization - regulated			(2,126,460		)	(2,020,253		)
	Net property, plant and equipment			$	12,297,504		$	10,114,340
	The average depreciation rates for our regulated property are set forth, by segment, in the following table for the periods indicated:
			Years Ended December 31,
	Regulated Property		2013	2012		2011
	ONEOK Partners		2.0% - 2.2%	1.9% - 2.2%		1.9% - 2.2%
	Natural Gas Distribution		2.0% - 3.0%	2.0% - 3.0%		2.0% - 2.9%
	We and ONEOK Partners incurred liabilities for construction work in process that had not been paid at December 31, 2013, 2012 and 2011 of $237.2 million, $228.5 million and $155.7 million, respectively. Such amounts are not included in capital expenditures (less allowance for equity funds used during construction) on the Consolidated Statements of Cash Flows.

GOODWILL_AND_INTANGIBLE_ASSETS

GOODWILL AND INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
GOODWILL AND INTANGIBLE ASSETS	'
	G.	GOODWILL AND INTANGIBLE ASSETS
	Goodwill - The following table sets forth our goodwill by segment for the periods indicated:
		ONEOK				Natural Gas				Energy		Total
		Partners				Distribution				Services
		(Thousands of dollars)
	31-Dec-12	$	433,535			$	157,953			$	—	$	591,488
	Acquisitions	92,000				—				—		92,000
	31-Dec-13	$	525,535			$	157,953			$	—	$	683,488
	As a result of our 2012 interim impairment assessment of our Energy Services segment’s goodwill, goodwill with a carrying amount of $10.3 million was written down to its implied fair value of zero, with a resulting impairment charge of $10.3 million recorded in 2012 earnings. For the remaining segments, Natural Gas Distribution and ONEOK Partners, there were no impairment indicators as the cash flows generated from each of these segments are derived from predominately fee-based, nondiscretionary services. There were no impairment charges resulting from our 2013 or 2011 annual impairment tests.
	Intangible Assets - The following table sets forth the gross carrying amount and accumulated amortization of intangible assets for the periods indicated:
			December 31,				December 31,
			2013				2012
			(Thousands of dollars)
	Gross intangible assets		$	565,215			$	462,214
	Accumulated amortization		(66,188		)		(57,496		)
	Net intangible assets		$	499,027			$	404,718
	At December 31, 2013 and 2012, our ONEOK Partners segment has $343.5 million and $249.2 million, respectively, of intangible assets related primarily to contracts acquired through acquisition, which are being amortized over a period of 20 to 40 years.  The remaining intangible asset balance has an indefinite life.  Amortization expense for intangible assets for 2013, 2012 and 2011 was $8.7 million, $7.7 million and $7.7 million, respectively, and the aggregate amortization expense for each of the next five years is estimated to be approximately $11.3 million.
	Acquisition - On September 30, 2013, ONEOK Partners completed the acquisition of a business, the Sage Creek acquisition. Included in this acquisition were supply contracts with acreage dedications and customer relationships that were included as intangible assets of $103 million in the purchase price allocation. The $92 million excess of purchase price over the fair value of the identifiable assets acquired was recorded as goodwill. For additional information related to the acquisition, see Note Q of the Notes to Consolidated Financial Statements in this Annual Report.

CREDIT_FACILITIES_AND_SHORTTER

CREDIT FACILITIES AND SHORT-TERM NOTES PAYABLE CREDIT FACILITIES AND SHORT-TERM NOTES PAYABLE (Notes)	12 Months Ended
	Dec. 31, 2013
CREDIT FACILITIES AND SHORT-TERM NOTES PAYABLE [Abstract]	'
Short-term Debt [Text Block]	'
	H.	CREDIT FACILITIES AND SHORT-TERM NOTES PAYABLE
	ONEOK Credit Agreement - At December 31, 2013, the ONEOK Credit Agreement contained certain financial, operational and legal covenants.  Among other things, these covenants included maintaining ONEOK’s stand-alone debt-to-capital ratio of no more than 67.5 percent at the end of any calendar quarter, limitations on the ratio of indebtedness secured by liens and indebtedness of subsidiaries to consolidated net tangible assets, a requirement that ONEOK maintains the power to control the management and policies of ONEOK Partners, and a limit on new investments in master limited partnerships. The ONEOK Credit Agreement also contained customary affirmative and negative covenants, including covenants relating to liens, investments, fundamental changes in the nature of ONEOK’s businesses, transactions with affiliates, the use of proceeds and a covenant that limits ONEOK’s ability to restrict its subsidiaries’ ability to pay dividends.  The debt covenant calculations in the ONEOK Credit Agreement excluded the debt of ONEOK Partners.  In the event of a breach of certain covenants by ONEOK, amounts outstanding under the ONEOK Credit Agreement may become due and payable immediately. At December 31, 2013, ONEOK’s stand-alone debt-to-capital ratio, as defined by the ONEOK Credit Agreement, was 48.3 percent, and ONEOK was in compliance with all covenants under the ONEOK Credit Agreement.
	At December 31, 2013, ONEOK had $564.5 million of commercial paper outstanding and $2.2 million in letters of credit issued. ONEOK is terminating its commercial paper program in conjunction with the separation of its natural gas distribution business.
	The weighted-average interest rate on ONEOK’s short-term debt outstanding was 0.39 percent and 0.46 percent at December 31, 2013 and 2012, respectively.
	The ONEOK Credit Agreement was amended, effective upon the separation of our natural gas distribution business on January 31, 2014, and will expire in January 2019. This amendment reduces the size of our credit facility to $300 million from $1.2 billion and contains certain financial, operational and legal covenants.  Among other things, these covenants include maintaining a ratio of indebtedness to Consolidated EBITDA (EBITDA, as defined in our ONEOK Credit Agreement) of no more than 4.0 to 1. Upon breach of certain covenants by us in our ONEOK Credit Agreement, amounts outstanding under our ONEOK Credit Agreement, if any, may become due and payable immediately.
	This amendment includes a $50 million sublimit for the issuance of standby letters of credit and a $50 million sublimit for swingline loans.  Under the terms of the ONEOK Credit Agreement, as amended, ONEOK may request an increase the size of the facility to an aggregate of $500 million from $300 million by either commitments from new lenders or increased commitments from existing lenders.  The ONEOK Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in our credit rating. Based on our current credit rating, borrowings, if any, will accrue at LIBOR plus 125 basis points, and the annual facility fee is 25 basis points.
	ONEOK Partners Credit Agreement - The ONEOK Partners Credit Agreement is available for general partnership purposes, including repayment of ONEOK Partners’ commercial paper notes, if necessary. Amounts outstanding under ONEOK Partners’ commercial paper program reduce the borrowing capacity under the ONEOK Partners Credit Agreement. At December 31, 2013, ONEOK Partners had no commercial paper outstanding, no letters of credit issued and no borrowings under the ONEOK Partners Credit Agreement.
	In December 2013, ONEOK Partners amended and restated the ONEOK Partners Credit Agreement effective on January 31, 2014, to increase the size of the facility to $1.7 billion from $1.2 billion. This amendment includes a $100 million sublimit for the issuance of standby letters of credit, a $150 million swingline sublimit and an option to request an increase in the size of the facility to an aggregate of $2.4 billion from $1.7 billion by either commitments from new lenders or increased commitments from existing lenders.
	The ONEOK Partners Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in ONEOK Partners’ credit rating. In 2013, borrowings under the ONEOK Partners Credit Agreement accrued interest at LIBOR plus 130 basis points, and the annual facility fee was 20 basis points based on ONEOK Partners’ current credit rating. Under the terms of the ONEOK Partners Credit Agreement, as amended in 2014, based on ONEOK Partners’ current credit rating, borrowings, if any, will accrue at LIBOR plus 117.5 basis points, and the annual facility fee is 20 basis points. The ONEOK Partners Credit Agreement is guaranteed fully and unconditionally by ONEOK Partners’ wholly owned subsidiary, the Intermediate Partnership. Borrowings under ONEOK Partners Credit Agreement are nonrecourse to ONEOK.
	The ONEOK Partners Credit Agreement contains certain financial, operational and legal covenants that remained substantially the same with the amendment. Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in ONEOK Partners 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. If ONEOK Partners consummates one or more acquisitions in which the aggregate purchase price is $25 million or more, the allowable ratio of indebtedness to adjusted EBITDA will increase to 5.5 to 1 for the quarter of the acquisition and the two following quarters. As a result of ONEOK Partners completing the Sage Creek acquisition on September 30, 2013, and acquiring the remaining 30 percent interest in its Maysville natural gas processing facility in the fourth quarter 2013, the allowable ratio of indebtedness to adjusted EBITDA increased to 5.5 to 1 and will remain at that level through the second quarter 2014. Upon breach of certain covenants by ONEOK Partners in the ONEOK Partners Credit Agreement, amounts outstanding, if any, may become due and payable immediately. At December 31, 2013, ONEOK Partners’ ratio of indebtedness to adjusted EBITDA was 4.0 to 1, and ONEOK Partners was in compliance with all covenants under the ONEOK Partners Credit Agreement.
	Neither ONEOK nor ONEOK Partners guarantees the debt or other similar commitments of unaffiliated parties. ONEOK does not guarantee the debt, commercial paper or other similar commitments of ONEOK Partners, and ONEOK Partners does not guarantee the debt, commercial paper or other similar commitments of ONEOK.
	ONE Gas Credit Agreement - In December 2013, ONE Gas entered into the ONE Gas Credit Agreement, which became effective upon the separation of the natural gas distribution business on January 31, 2014, and is scheduled to expire in January 2019. The ONE Gas Credit Agreement contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining ONE Gas’s debt-to-capital ratio of no more than 70 percent at the end of any calendar quarter. The ONE Gas Credit Agreement also contains customary affirmative and negative covenants, including covenants relating to liens, indebtedness of subsidiary, investments, changes in the nature of business, fundamental changes, transactions with affiliates, burdensome agreements and use of proceeds. In the event of a breach of certain covenants by ONE Gas, amounts outstanding under the ONE Gas Credit Agreement may become due and payable immediately.
	The ONE Gas Credit Agreement includes a $50 million sublimit for the issuance of standby letters of credit and also features an option to request an increase in the size of the facility to an aggregate of $1.2 billion from $700 million by either commitments from new lenders or increased commitments from existing lenders.  The ONE Gas Credit Agreement is available for general corporate purposes.  The ONE Gas Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in ONE Gas’ credit rating.  Based on ONE Gas’ current credit rating, borrowings, if any, will accrue at LIBOR plus 79.5 basis points, and the annual facility fee is 8 basis points.
	Upon completion of the separation on January 31, 2014, ONEOK’s obligations related to the ONE Gas Credit Agreement terminated.

LONGTERM_DEBT

LONG-TERM DEBT	12 Months Ended
	Dec. 31, 2013
Long-term Debt, Unclassified [Abstract]	'
LONG-TERM DEBT	'
	I.	LONG-TERM DEBT
	All notes are senior unsecured obligations, ranking equally in right of payment with all of our existing and future unsecured senior indebtedness.  The following table sets forth our long-term debt for the periods indicated:
			December 31,			December 31,
			2013			2012
			(Thousands of dollars)
	ONEOK
	$400,000 at 5.2% due 2015		$	400,000		$	400,000
	$700,000 at 4.25% due 2022		700,000			700,000
	$100,000 at 6.5% due 2028		87,649			87,662
	$100,000 at 6.875% due 2028		100,000			100,000
	$400,000 at 6.0% due 2035		400,000			400,000
	Other		1,323			1,528
	Total ONEOK senior notes payable		1,688,972			1,689,190
	ONEOK Partners
	$650,000 at 3.25% due 2016		650,000			650,000
	$450,000 at 6.15% due 2016		450,000			450,000
	$400,000 at 2.0% due 2017		400,000			400,000
	$425,000 at 3.2% due 2018		425,000			—
	$500,000 at 8.625% due 2019		500,000			500,000
	$900,000 at 3.375 % due 2022		900,000			900,000
	$425,000 at 5.0 % due 2023		425,000			—
	$600,000 at 6.65% due 2036		600,000			600,000
	$600,000 at 6.85% due 2037		600,000			600,000
	$650,000 at 6.125% due 2041		650,000			650,000
	$400,000 at 6.2% due 2043		400,000			—
	Guardian Pipeline
	Average 7.85%, due 2022		67,208			74,857
	Total ONEOK Partners senior notes payable		6,067,208			4,824,857
	Total long-term notes payable		7,756,180			6,514,047
	Unamortized portion of terminated swaps		25,340			27,058
	Unamortized debt discount		(15,889		)	(14,878		)
	Current maturities		(10,656		)	(10,855		)
	Long-term debt		$	7,754,975		$	6,515,372
	The aggregate maturities of long-term debt outstanding for the years 2014 through 2018 are shown below:
			ONEOK			ONEOK			Guardian		Total
						Partners			Pipeline
			(Millions of dollars)
	2014		$	3		$	—		$	7.7	$	10.7
	2015		$	403		$	—		$	7.7	$	410.7
	2016		$	3		$	1,100.00		$	7.7	$	1,110.70
	2017		$	3		$	400		$	7.7	$	410.7
	2018		$	3		$	425		$	7.7	$	435.7
	Additionally, our senior notes due 2028 (6.5 percent) are callable at par at our option from now until maturity.
	ONE Gas Debt Issuance - In January 2014, ONE Gas completed a private placement of three series of senior notes aggregating $1.2 billion, consisting of $300 million of five-year senior notes at 2.07 percent; $300 million of 10-year senior notes at 3.61 percent; and $600 million of 30-year senior notes at 4.658 percent. ONE Gas received approximately $1.19 billion from the offering, net of issuance costs.
	ONEOK Debt Repayment - ONE Gas made a cash payment to ONEOK of approximately $1.13 billion from the proceeds of the ONE Gas senior notes offering. In February 2014, we retired approximately $152.5 million of the 4.25 percent senior notes due 2022 through a tender offer. The total amount paid, including fees and other charges, was approximately $150 million.
	In February 2014, we made an irrevocable election to exercise the make-whole call on our $400 million, 5.2 percent senior notes due in 2015. The full repayment is expected to occur in March 2014 and is estimated to be approximately $429 million, including accrued but unpaid interest to the redemption date.
	ONEOK Debt Issuance - In January 2012, we completed an underwritten public offering of $700 million, 4.25 percent senior notes due 2022.  The net proceeds from the offering, after deducting underwriting discounts and offering expenses, of approximately $694.3 million were used to repay amounts outstanding under our commercial paper program and for general corporate purposes.
	ONEOK Debt Covenants - The indentures governing ONEOK’s senior notes due 2028 (6.5 percent and 6.875 percent) include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2015, 2022 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more.  Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2015, 2022, 2028 and 2035 to declare those senior notes immediately due and payable in full.
	ONEOK may redeem the senior notes due 2015, 2028 (6.875 percent) and 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the senior notes due 2028 (6.5 percent), in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest.  ONEOK may redeem the remaining balance of its 4.25 percent senior notes due 2022 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three months before the maturity date.  Prior to this date, ONEOK may redeem these senior notes on the same basis as its other senior notes due 2015, 2028 (6.875 percent) and 2035.  The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.  ONEOK’s senior notes due 2015, 2022, 2028 and 2035 are senior unsecured obligations, ranking equally in right of payment with all of ONEOK’s existing and future unsecured senior indebtedness.
	ONEOK Partners’ Debt Issuance and Maturities - In September 2013, ONEOK Partners completed an underwritten public offering of $1.25 billion of senior notes, consisting of $425 million, 3.2 percent senior notes due 2018, $425 million, 5.0 percent senior notes due 2023 and $400 million, 6.2 percent senior notes due 2043. A portion of the net proceeds from the offering of approximately $1.24 billion was used to repay amounts outstanding under its commercial paper program, and the balance will be used for general partnership purposes, including but not limited to capital expenditures.
	In September 2012, ONEOK Partners completed an underwritten public offering of $1.3 billion of senior notes, consisting of $400 million, 2.0 percent senior notes due 2017 and $900 million, 3.375 percent senior notes due 2022. A portion of the net proceeds from the offering of approximately $1.29 billion was used to repay amounts outstanding under its commercial paper program, and the balance was used for general partnership purposes, including but not limited to capital expenditures.
	ONEOK Partners repaid its $350 million, 5.9 percent senior notes at maturity in April 2012 with a portion of the proceeds from its March 2012 equity earnings.
	ONEOK Partners’ Debt Covenants - ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partners’ ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partners’ outstanding senior notes to declare those notes immediately due and payable in full.
	ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.  The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.  ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partners’ may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners’ may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.  ONEOK Partners’ senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partners’ existing and future unsecured senior indebtedness, and are structurally subordinate to any of the existing and future debt and other liabilities of any nonguarantor subsidiaries.  ONEOK Partners’ senior notes are nonrecourse to ONEOK.
	ONEOK Partners’ Debt Guarantee - ONEOK Partners’ senior notes are guaranteed on a senior unsecured basis by the Intermediate Partnership.  The Intermediate Partnership’s guarantee is full and unconditional, subject to certain customary automatic release provisions.  The guarantee ranks equally in right of payment to all of the Intermediate Partnership’s existing and future unsecured senior indebtedness.  ONEOK Partners, L.P. has no significant assets or operations other than its investment in the Intermediate Partnership, which is also consolidated.  At December 31, 2013, the Intermediate Partnership held the equity of ONEOK Partners’ subsidiaries, as well as a 50 percent interest in Northern Border Pipeline.  ONEOK Partners’ long-term debt is nonrecourse to ONEOK.
	Guardian Pipeline Senior Notes - These senior notes were issued under a master shelf agreement dated November 8, 2001, with certain financial institutions.  Principal payments are due quarterly through 2022. These senior notes contain financial covenants that require the maintenance of certain ratios defined in the master shelf agreement based on Guardian Pipeline’s financial position and results of operations.  Upon any breach of these covenants, all amounts outstanding under the master shelf agreement may become due and payable immediately.  At December 31, 2013, Guardian Pipeline was in compliance with its financial covenants.
	Interest-rate Swaps - See Note E for a discussion of our interest-rate swaps.
	Other - We amortize premiums, discounts and expenses incurred in connection with the issuance of long-term debt consistent with the terms of the respective debt instrument.

EQUITY

EQUITY	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
EQUITY	'
	J.	EQUITY
	Series A and B Convertible Preferred Stock - There are no shares of Series A or Series B Preferred Stock currently issued or outstanding.
	Series C Preferred Stock - The Series C Preferred Stock (Series C) was issuable in connection with our now expired ONEOK Rights Agreement, which was designed to protect our shareholders from coercive or unfair takeover tactics.  No shares of Series C were issued, and the ONEOK Rights Agreement expired February 4, 2013, and was not renewed.
	Common Stock - At December 31, 2013, we had approximately 362.4 million shares of authorized and unreserved common stock available for issuance.
	Dividends - Dividends paid totaled $304.7 million, $262.0 million and $227.0 million for 2013, 2012 and 2011, respectively. The following table sets forth the quarterly dividends per share declared and paid on our common stock for the periods indicated:
			Years Ended December 31,
			2013		2012		2011
	First Quarter		$	0.36	$	0.305	$	0.26
	Second Quarter		$	0.36	$	0.305	$	0.26
	Third Quarter		$	0.38	$	0.33	$	0.28
	Fourth Quarter		$	0.38	$	0.33	$	0.28
	Total		$	1.48	$	1.27	$	1.08
	Additionally, a quarterly dividend of $0.40 per share was declared in January 2014, payable in the first quarter 2014.
	Stock Repurchase Program - Our three-year stock repurchase program, which expired on December 31, 2013, was authorized by our Board of Directors in October 2010 to buy up to $750 million of our common stock.  We executed a $300 million repurchase of approximately 8.6 million shares in 2011, a $150 million repurchase of approximately 3.4 million shares in September 2012 and did not repurchase any shares of our common stock in 2013.
	See Note Q for a discussion of ONEOK Partners’ issuance of common units and distributions to noncontrolling interests.

ACCUMULATED_OTHER_COMPREHENSIV

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	12 Months Ended
	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	'
	K.	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)
	The following table sets forth the balance in accumulated other comprehensive income (loss) for the periods indicated:
		Unrealized Gains				Unrealized			Pension and			Accumulated
		(Losses) on Energy				Holding Gains			Postretirement			Other
		Marketing and				(Losses)			Benefit Plan			Comprehensive
		Risk-Management				on Investment			Obligations (a)			Income (Loss) (a)
		Assets/Liabilities (a)				Securities (a)
		(Thousands of dollars)
	1-Jan-12	$	(55,367	)		$	987		$	(151,741	)	$	(206,121	)
	Other comprehensive income (loss) before	16,709				47			(47,004		)	(30,248		)
	reclassifications
	Amounts reclassified from accumulated other	(16,372		)		—			35,943			19,571
	comprehensive income (loss)
	Other comprehensive income	337				47			(11,061		)	(10,677		)
	(loss) attributable to ONEOK
	31-Dec-12	(55,030		)		1,034			(162,802		)	(216,798		)
	Other comprehensive income (loss) before	8,842				(177		)	37,144			45,809
	reclassifications
	Amounts reclassified from accumulated other	3,020				—			45,982			49,002
	comprehensive income (loss)
	Other comprehensive income	11,862				(177		)	83,126			94,811
	(loss) attributable to ONEOK
	31-Dec-13	$	(43,168	)		$	857		$	(79,676	)	$	(121,987	)
	(a) All amounts are presented net of tax.
	The following table sets forth the effect of reclassifications from accumulated other comprehensive income (loss) on our Consolidated Statements of Income for the period indicated:
		Details about Accumulated Other		Year Ended December 31, 2013				Affected Line Item
		Comprehensive Income (Loss) Components						in the Consolidated
								Statements of Income
				(Thousands of dollars)
		Unrealized (gains) losses on energy marketing and risk-
		management assets/liabilities
		Commodity contracts		$	(19,049	)		Revenues
		Commodity contracts		14,320				Cost of sales and fuel
		Interest-rate contracts		14,560				Interest expense
				9,831				Income before income taxes
				(1,905		)		Income tax expense
				7,926				Net income
		Noncontrolling interest		4,906				Less: Net income attributable to
								noncontrolling interest
				$	3,020			Net income attributable to ONEOK
		Pension and postretirement benefit plan obligations (a)
		Amortization of net loss		$	78,887
		Amortization of unrecognized prior service cost		(5,522		)
		Amortization of unrecognized net asset at adoption		284
		Settlement charge		1,338
				74,987				Income before income taxes
				(29,005		)		Income tax expense
				$	45,982			Net income attributable to ONEOK
		Total reclassifications for the period attributable to ONEOK		$	49,002			Net income attributable to ONEOK
	(a) These components of accumulated other comprehensive income (loss) are included in the computation of net periodic benefit cost. See Note N for additional detail of our net periodic benefit cost.

EARNINGS_PER_SHARE

EARNINGS PER SHARE	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
EARNINGS PER SHARE	'
	L.	EARNINGS PER SHARE
	The following tables set forth the computation of basic and diluted EPS from continuing operations for the periods indicated:
			Year Ended December 31, 2013
			Income		Shares	Per Share
						Amount
			(Thousands, except per share amounts)
	Basic EPS from continuing operations
	Income from continuing operations attributable to ONEOK available for		$	266,533	206,044	$	1.29
	common stock
	Diluted EPS from continuing operations
	Effect of options and other dilutive securities		—		3,651
	Income from continuing operations attributable to ONEOK available for		$	266,533	209,695	$	1.27
	common stock and common stock equivalents
			Year Ended December 31, 2012
			Income		Shares	Per Share
						Amount
			(Thousands, except per share amounts)
	Basic EPS from continuing operations
	Income from continuing operations attributable to ONEOK available for		$	346,340	206,140	$	1.68
	common stock
	Diluted EPS from continuing operations
	Effect of options and other dilutive securities		—		4,570
	Income from continuing operations attributable to ONEOK available for		$	346,340	210,710	$	1.64
	common stock and common stock equivalents
			Year Ended December 31, 2011
			Income		Shares	Per Share
						Amount
			(Thousands, except per share amounts)
	Basic EPS from continuing operations
	Income from continuing operations attributable to ONEOK available for		$	358,364	209,344	$	1.71
	common stock
	Diluted EPS from continuing operations
	Effect of options and other dilutive securities		—		5,154
	Income from continuing operations attributable to ONEOK available for		$	358,364	214,498	$	1.67
	common stock and common stock equivalents
	There were no option shares excluded from the calculation of diluted EPS for 2013, 2012 and 2011.

SHAREBASED_PAYMENTS

SHARE-BASED PAYMENTS	12 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
SHARE-BASED PAYMENTS	'
	M.	SHARE-BASED PAYMENTS
	The ONEOK, Inc. Equity Compensation Plan (ECP) and the ONEOK, Inc. Long-Term Incentive Plan (LTIP) provide for the granting of stock-based compensation, including incentive stock options, nonstatutory stock options, stock bonus awards, restricted stock awards, restricted stock-unit awards, performance stock awards and performance-unit awards to eligible employees and the granting of stock awards to nonemployee directors. We have reserved 10.0 million and 15.6 million shares of common stock for issuance under the ECP and LTIP, respectively. At December 31, 2013, we had approximately 2.0 million and 0.9 million shares available for issuance under the ECP and LTIP, respectively, which reflect shares issued and estimated shares expected to be issued upon vesting of outstanding awards granted under these plans, less forfeitures.  These plans allow for the deferral of awards granted in stock or cash, in accordance with Internal Revenue Code section 409A requirements.
	Restricted Stock Units - We have granted restricted stock units to key employees that vest over a three-year period and entitle the grantee to receive shares of our common stock.  Restricted stock unit awards are measured at fair value as if they were vested and issued on the grant date, reduced by expected dividend payments and adjusted for estimated forfeitures.  No dividends were paid prior to vesting on the restricted stock units granted prior to 2013.  Beginning in 2013, restricted stock unit awards granted accrue dividend equivalents in the form of additional restricted stock units prior to vesting. Compensation expense is recognized on a straight-line basis over the vesting period of the award.
	Performance-Unit Awards - We have granted performance-unit awards to key employees.  The shares of our common stock underlying the performance units vest at the expiration of a period determined by the Executive Compensation Committee if certain performance criteria are met by the company.  Outstanding performance units vest at the expiration of a three-year period.  Upon vesting, a holder of performance units is entitled to receive a number of shares of our common stock equal to a percentage (0 percent to 200 percent) of the performance units granted, based on our total shareholder return over the vesting period, compared with the total shareholder return of a peer group of other energy companies over the same period. Compensation expense is recognized on a straight-line basis over the period of the award.
	If paid, the outstanding performance unit awards entitle the grantee to receive the grant in shares of our common stock.  Our outstanding performance unit awards are equity awards with a market-based condition, which results in the compensation cost for these awards being recognized over the requisite service period, provided that the requisite service period is fulfilled, regardless of when, if ever, the market condition is satisfied.  The fair value of these performance units was estimated on the grant date based on a Monte Carlo model. No dividends were paid prior to vesting on performance stock units granted prior to 2013. Beginning in 2013, performance stock unit awards granted accrue dividend equivalents in the form of additional performance units prior to vesting. The compensation expense on these awards only will be adjusted for changes in forfeitures.
	Options - No stock options have been granted since 2003. Stock option activity was not material in 2013, 2012 and 2011. All previously issued stock options expired or were exercised as of February 2013.
	Stock Compensation Plan for Non-Employee Directors
	The ONEOK, Inc. Stock Compensation Plan for Non-Employee Directors (the DSCP) provides for the granting of stock options, stock bonus awards, including performance-unit awards, restricted stock awards and restricted stock unit awards. Under the DSCP, these awards may be granted by the Executive Compensation Committee at any time, until grants have been made for all shares authorized under the DSCP.  We have reserved a total of 1.4 million shares of common stock for issuance under the DSCP, and at December 31, 2013, we had approximately 1.0 million shares available for issuance under the plan. The maximum number of shares of common stock that can be issued to a participant under the DSCP during any year is 40,000. No performance unit awards or restricted stock awards have been made to nonemployee directors under the DSCP.
	General
	For all awards outstanding, we used a 3 percent forfeiture rate based on historical forfeitures under our share-based payment plans. We primarily use treasury stock to satisfy our share-based payment obligations.
	Compensation cost expensed for our share-based payment plans described above was $28.6 million, $22.6 million and $40.7 million during 2013, 2012 and 2011, respectively, which is $17.6 million, $14.2 million and $25.7 million, net of tax benefits, respectively. Capitalized share-based compensation cost was not material for 2013, 2012 and 2011.
	Cash received from the exercise of awards under all share-based payment arrangements was not material for 2013, 2012 and 2011.  The tax benefit realized for the anticipated tax deductions of the exercise of share-based payment arrangements was not material for 2013, 2012 and 2011.
	Restricted Stock Unit Activity
	As of December 31, 2013, we had $9.3 million of total unrecognized compensation cost related to our nonvested restricted stock unit awards, which is expected to be recognized over a weighted-average period of 1.7 years years.  The following tables set forth activity and various statistics for our restricted stock unit awards:
			Number of			Weighted
			Shares			Average Price
	Nonvested December 31, 2012		1,020,600			$	27.21
	Granted		167,301			$	47.46
	Released to participants		(384,883	)		$	19.06
	Forfeited		(26,422	)		$	37.23
	Nonvested December 31, 2013		776,596			$	35.27
			2013				2012		2011
	Weighted-average grant date fair value (per share)		$	47.46			$	36.65	$	28.5
	Fair value of shares granted (thousands of dollars)		$	7,940			$	11,030	$	11,728
	Performance-Unit Activity
	As of December 31, 2013, we had $22.5 million of total unrecognized compensation cost related to the nonvested performance-unit awards, which is expected to be recognized over a weighted-average period of 1.7 years.  The following tables set forth activity and various statistics related to the performance-unit awards and the assumptions used in the valuations of the 2013, 2012 and 2011 grants at the grant date:
			Number of			Weighted
			Units			Average Price
	Nonvested December 31, 2012		2,133,157			$	32.74
	Granted		377,200			$	52.34
	Released to participants		(801,354	)		$	24.05
	Forfeited		(56,858	)		$	42.53
	Nonvested December 31, 2013		1,652,145			$	41.1
			2013		2012		2011
	Volatility (a)		22.27%		27.00%		39.91%
	Dividend Yield		3.04%		2.86%		3.30%
	Risk-free Interest Rate		0.42%		0.38%		1.33%
	(a) - Volatility was based on historical volatility over three years using daily stock price observations.
			2013				2012		2011
	Weighted-average grant date fair value (per share)		$	52.34			$	42.39	$	34.68
	Fair value of shares granted (thousands of dollars)		$	19,742			$	25,466	$	29,186
	Employee Stock Purchase Plan
	We have reserved a total of 11.6 million shares of common stock for issuance under our ONEOK, Inc. Employee Stock Purchase Plan (the ESPP).  Subject to certain exclusions, all full-time employees are eligible to participate in the ESPP. Employees can choose to have up to 10 percent of their annual base pay withheld to purchase our common stock, subject to terms and limitations of the plan.  The Executive Compensation Committee may allow contributions to be made by other means, provided that in no event will contributions from all means exceed 10 percent of the employee’s annual base pay.  The purchase price of the stock is 85 percent of the lower of its grant date or exercise date market price.  Approximately 52 percent, 55 percent and 56 percent of employees participated in the plan in 2013, 2012 and 2011, respectively. Compensation expense for the ESPP was $6.6 million and $7.2 million in 2013 and 2011, respectively, and was not material in 2012. Under the plan, we sold 254,960 shares at $35.97 in 2013, 256,490 shares at $35.97 per share in 2012 and 365,116 shares at $23.70 per share in 2011.
	Employee Stock Award Program
	Under our Employee Stock Award Program, we issued, for no monetary consideration, to all eligible employees one share of our common stock when the per-share closing price of our common stock on the NYSE was for the first time at or above $13 per share.  The total number of shares of our common stock available for issuance under this program was 900,000.  Shares issued to employees under this program during 2013, 2012 and 2011 totaled 63,975, 42,467 and 295,694 respectively, and compensation expense related to the Employee Stock Award Plan was $3.6 million, $1.9 million and $16.0 million in 2013, 2012 and 2011, respectively.
	Deferred Compensation Plan for Non-Employee Directors
	The ONEOK, Inc. Nonqualified Deferred Compensation Plan for Non-Employee Directors provides our nonemployee directors the option to defer all or a portion of their compensation for their service on our Board of Directors.  Under the plan, directors may elect either a cash deferral option or a phantom stock option.  Under the cash deferral option, directors may defer the receipt of all or a portion of their annual retainer fees, plus accrued interest.  Under the phantom stock option, directors may defer all or a portion of their annual retainer fees and receive such fees on a deferred basis in the form of shares of common stock under our Long-Term Incentive Plan or Equity Compensation Plan.  Shares are distributed to nonemployee directors at the fair market value of our common stock at the date of distribution.
	Impact of ONE Gas Separation on Stock Compensation Plans
	In connection with the separation of the natural gas distribution business on January 31, 2014, ONEOK entered into an Employee Matters Agreement with ONE Gas, which provides that employees of ONE Gas no longer participate in stock compensation plans sponsored or maintained by ONEOK. Pursuant to the Employee Matters Agreement, we made certain adjustments to the number of our share-based compensation awards, with the intention of preserving the intrinsic value of each award immediately prior to the separation.
	Restricted Stock Units - Restricted stock units were converted to awards in shares of the entity where the employee holding them was assigned following the separation. Therefore, restricted stock units held by an employee who separated with ONE Gas were surrendered as a result of the separation; these ONE Gas employees were granted awards by ONE Gas that are equal in value to their surrendered ONEOK shares. The number of restricted stock units held by employees who remained with ONEOK was adjusted by issuing additional units to preserve the intrinsic value of the awards immediately prior to the separation. The additional shares granted by ONEOK and the shares surrendered by ONE Gas employees resulted in a net decrease of approximately 77 thousand nonvested, restricted stock unit awards and a decrease of approximately $2.4 million in unrecognized compensation costs.
	Performance-Unit Awards - Performance-unit awards held by an employee who separated with ONE Gas were surrendered as a result of the separation, and new performance-unit awards were concurrently granted by ONE Gas with an equivalent intrinsic value of the intrinsic value of the ONEOK awards immediately prior to the separation. The number of performance unit awards held by employees who remained with ONEOK was adjusted by issuing additional units to preserve the intrinsic value of the awards immediately prior to the separation. The additional shares granted by ONEOK and the shares surrendered by ONE Gas employees resulted in a net decrease of approximately 151 thousand nonvested performance-unit awards and a decrease of approximately $5.6 million in unrecognized compensation costs.
	Employee Stock Purchase Plan - For those employees who separated with ONE Gas, enrollment in the plan was terminated upon the separation. Employees who separated with ONE Gas will receive shares of ONEOK common stock at the end of the offering period based upon the contributions made while employed at ONEOK. There was no impact to enrollment for those employees who remained at ONEOK. The grant date market price for ONEOK stock will be adjusted to reflect the impact of the distribution of ONE Gas shares.
	Deferred Awards - Deferred shares associated with vested restricted stock unit awards or performance unit awards held by directors or employees were treated in the same manner as regular shareholders, by crediting one deferred share of ONE Gas stock for every four deferred shares of ONEOK stock.

EMPLOYEE_BENEFIT_PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 31, 2013
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]	'
EMPLOYEE BENEFIT PLANS	'
	N.	EMPLOYEE BENEFIT PLANS
	Retirement and Postretirement Benefit Plans
	Retirement Plans - We have a defined benefit pension plan covering nonbargaining unit employees hired before January 1, 2005, and certain bargaining-unit employees hired before December 15, 2011.  Nonbargaining unit employees hired after December 31, 2004; employees represented by Local No. 304 of the IBEW hired on or after July 1, 2010; employees represented by the United Steelworkers hired on or after December 15, 2011; and employees who accepted a one-time opportunity to opt out of our pension plan, are covered by our Profit-Sharing Plan.  In addition, we have a supplemental executive retirement plan for the benefit of certain officers.  No new participants in our supplemental executive retirement plan have been approved since 2005, and effective January 2014 the plan formally was closed to new participants.  We fund our pension costs at a level needed to maintain or exceed the minimum funding levels required by the Employee Retirement Income Security Act of 1974, as amended, and the Pension Protection Act of 2006.
	Postretirement Benefit Plans - We sponsor health and welfare plans that provide postretirement medical and life insurance benefits to certain employees who retire with at least five years of service.  The postretirement medical plan is contributory based on hire date, age and years of service, with retiree contributions adjusted periodically, and contains other cost-sharing features such as deductibles and coinsurance.
	In December 2011, we announced to participants a change from a self-insured postretirement medical plan to a fully insured solution for plan participants who are medicare eligible.  This announcement resulted in a $44.6 million reduction in our accumulated postretirement benefit obligation that was recognized in other comprehensive income and will be amortized to net periodic benefit cost over the expected remaining years of service for plan participants.
	Regulatory Treatment - The OCC, KCC and regulatory authorities in Texas have approved the recovery of pension costs and postretirement benefits costs through rates for Oklahoma Natural Gas, Kansas Gas Service and Texas Gas Service, respectively. The costs recovered through rates are based on current funding requirements and the net periodic benefit cost for pension and postretirement costs.  Differences, if any, between the expense and the amount recovered through rates are reflected in earnings, net of authorized deferrals.
	Our regulated entities historically have recovered pension and postretirement benefit costs through rates.  We believe it is probable that regulators will continue to include the net periodic pension and postretirement benefit costs in our regulated entities’ cost of service.  Accordingly, we have recorded a regulatory asset for the minimum liability associated with our regulated entities’ pension and postretirement benefit obligations that otherwise would have been recorded in accumulated other comprehensive income.
	Obligations and Funded Status - The following tables set forth our pension and postretirement benefit plans benefit obligations and fair value of plan assets for the periods indicated:
			Pension Benefits						Postretirement Benefits
			December 31,						December 31,
			2013			2012			2013			2012
	Change in Benefit Obligation		(Thousands of dollars)
	Benefit obligation, beginning of period		$	1,313,560		$	1,215,932		$	299,172		$	286,044
	Service cost		22,968			21,301			4,612			4,960
	Interest cost		54,449			59,237			11,713			13,893
	Plan participants’ contributions		—			—			4,293			5,851
	Actuarial loss (gain)		(110,552		)	105,732			(29,460		)	9,935
	Benefits paid		(58,976		)	(88,642		)	(18,411		)	(21,380		)
	Plan amendment		—			—			17,228			(131		)
	Benefit obligation, end of period		1,221,449			1,313,560			289,147			299,172
	Change in Plan Assets
	Fair value of plan assets, beginning of period		995,264			902,235			148,162			124,163
	Actual return on plan assets		176,889			90,026			27,483			14,273
	Employer contributions		—			91,881			866			10,728
	Benefits paid		(59,404		)	(88,878		)	(876		)	(1,002		)
	Fair value of assets, end of period		1,112,749			995,264			175,635			148,162
	Balance at December 31		$	(108,700	)	$	(318,296	)	$	(113,512	)	$	(151,010	)
	Current liabilities		$	(5,457	)	$	(4,695	)	$	—		$	—
	Noncurrent liabilities		(103,243		)	(313,601		)	(113,512		)	(151,010		)
	Balance at December 31		$	(108,700	)	$	(318,296	)	$	(113,512	)	$	(151,010	)
	The accumulated benefit obligation for our pension plans was $1,159.0 million and $1,240.3 million at December 31, 2013 and 2012, respectively.
	There are no plan assets expected to be withdrawn and returned to us in 2014.
	Components of Net Periodic Benefit Cost - The following tables set forth the components of net periodic benefit cost for our pension and postretirement benefit plans for the periods indicated:
			Pension Benefits
			Years Ended December 31,
			2013			2012			2011
			(Thousands of dollars)
	Components of net periodic benefit cost
	Service cost		$	22,968		$	21,301		$	20,013
	Interest cost		54,449			59,237			58,757
	Expected return on assets		(81,272		)	(82,756		)	(75,500		)
	Amortization of unrecognized prior service cost		920			969			1,018
	Amortization of net loss		66,282			48,439			35,708
	Settlements		1,338			1,401			—
	Net periodic benefit cost		$	64,685		$	48,591		$	39,996
			Postretirement Benefits
			Years Ended December 31,
			2013			2012			2011
			(Thousands of dollars)
	Components of net periodic benefit cost
	Service cost		$	4,612		$	4,960		$	4,987
	Interest cost		11,713			13,893			15,632
	Expected return on assets		(12,259		)	(10,687		)	(10,272		)
	Amortization of unrecognized net asset at adoption		284			2,874			3,189
	Amortization of unrecognized prior service cost		(6,442		)	(8,252		)	(2,518		)
	Amortization of net loss		12,605			13,184			8,123
	Net periodic benefit cost		$	10,513		$	15,972		$	19,141
	Other Comprehensive Income (Loss) - The following tables set forth the amounts recognized in other comprehensive income (loss) related to our pension benefits and postretirement benefits for the periods indicated:
			Pension Benefits
			Years Ended December 31,
			2013			2012			2011
			(Thousands of dollars)
	Regulatory asset gain (loss)		$	(110,437	)	$	67,472		$	114,625
Net gain (loss) arising during the period		201,251			(103,199		)	(182,987		)
Amortization of regulatory asset		(44,378		)	(32,527		)	(23,265		)
Amortization of prior service credit		920			969			1,018
Amortization of loss		67,620			49,839			35,708
Deferred income taxes		(44,473		)	6,748			21,236
Total recognized in other comprehensive income (loss)		$	70,503		$	(10,698	)	$	(33,665	)
		Postretirement Benefits
		Years Ended December 31,
		2013			2012			2011
		(Thousands of dollars)
Regulatory asset gain (loss)		$	(7,674	)	$	4,376		$	7,389
Net gain (loss) arising during the period		44,685			(6,348		)	(40,765		)
Amortization of regulatory asset		(5,643		)	(6,557		)	(7,214		)
Amortization of transition obligation		284			2,874			3,189
Amortization of prior service cost		(6,442		)	(8,252		)	(2,518		)
Amortization of loss		12,605			13,184			8,123
Plan amendment		(17,228		)	131			44,562
Deferred income taxes		(7,964		)	229			(4,938		)
Total recognized in other comprehensive income (loss)		$	12,623		$	(363	)	$	7,828
The table below sets forth the amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense for the periods indicated:
		Pension Benefits						Postretirement Benefits
		December 31,						December 31,
		2013			2012			2013			2012
		(Thousands of dollars)
Transition obligation		$	—		$	—		$	—		$	(283	)
Prior service credit (cost)		(1,102		)	(2,022		)	14,631			38,301
Accumulated loss		(415,375		)	(684,245		)	(59,362		)	(116,652		)
Accumulated other comprehensive loss		(416,477		)	(686,267		)	(44,731		)	(78,634		)
before regulatory assets
Regulatory asset for regulated entities		288,017			442,833			43,254			56,571
Accumulated other comprehensive loss		(128,460		)	(243,434		)	(1,477		)	(22,063		)
after regulatory assets
Deferred income taxes		49,689			94,161			572			8,534
Accumulated other comprehensive loss,		$	(78,771	)	$	(149,273	)	$	(905	)	$	(13,529	)
net of tax
The following table sets forth the amounts recognized in either accumulated comprehensive income (loss) or regulatory assets expected to be recognized as components of net periodic benefit expense in the next fiscal year. The table does not include amounts applicable to employees of ONE Gas, as those amounts are expected to be recognized by ONE Gas as a result of the separation of the natural gas distribution business.
		Pension			Postretirement
		Benefits			Benefits
Amounts to be recognized in 2014		(Thousands of dollars)
Transition obligation		$	—		$	—
Prior service credit (cost)		$	193		$	(1,662	)
Net loss		$	15,021		$	833
Actuarial Assumptions - The following table sets forth the weighted-average assumptions used to determine benefit obligations for pension and postretirement benefits for the periods indicated:
		Pension Benefits			Postretirement Benefits
		December 31,			December 31,
		2013		2012	2013		2012
Discount rate		5.25%		4.25%	5.00%		4.00%
Compensation increase rate		3.35% - 3.40%		3.45% - 3.50%	3.35% - 3.40%		3.45% - 3.50%
The following table sets forth the weighted-average assumptions used to determine net periodic benefit costs for the periods indicated:
		Years Ended December 31,
		2013		2012	2011
Discount rate - pension plans		4.25%		5.00%	5.50%
Discount rate - postretirement plans		4.00%		5.00%	5.50%
Expected long-term return on plan assets		8.25%		8.25%	8.25%
Compensation increase rate		3.45% - 3.50%		3.20% - 3.80%	3.30% - 3.90%
We determine our overall expected long-term rate of return on plan assets, based on our review of historical returns and economic growth models.
We determine our discount rates annually.  We estimate our discount rate based upon a comparison of the expected cash flows associated with our future payments under our pension and postretirement obligations to a hypothetical bond portfolio created using high-quality bonds that closely match expected cash flows.  Bond portfolios are developed by selecting a bond for each of the next 60 years based on the maturity dates of the bonds.  Bonds selected to be included in the portfolios are only those rated by Moody’s as AA- or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.
Health Care Cost Trend Rates - The following table sets forth the assumed health care cost-trend rates for the periods indicated:
		2013		2012
Health care cost-trend rate assumed for next year		4.0% - 8.25%		4.0% - 9.0%
Rate to which the cost-trend rate is assumed to decline		4.0% - 5.0%		4.0% - 5.0%
(the ultimate trend rate)
Year that the rate reaches the ultimate trend rate		2022		2022
Assumed health care cost-trend rates have an impact on the amounts reported for our health care plans.  A one percentage point change in assumed health care cost-trend rates would have the following effects:
		One Percentage			One Percentage
		Point Increase			Point Decrease
		(Thousands of dollars)
Effect on total of service and interest cost		$	1,136		$	(1,022	)
Effect on postretirement benefit obligation		$	15,152		$	(14,350	)
Plan Assets - Our investment strategy is to invest plan assets in accordance with sound investment practices that emphasize long-term fundamentals.  The goal of this strategy is to maximize investment returns while managing risk in order to meet the plan’s current and projected financial obligations.  The plan’s investments include a diverse blend of various domestic and international equities, investments in various classes of debt securities, insurance contracts and venture capital.  The target allocation for the assets of our pension plan is as follows:
U.S. large-cap equities		37	%
Aggregate bonds		24	%
Developed foreign large-cap equities		10	%
Alternative investments		8	%
Mid-cap equities		6	%
Emerging markets equities		5	%
Small-cap equities		4	%
High-yield bonds		3	%
Developed foreign bonds		2	%
Emerging market bonds		1	%
Total		100	%
As part of our risk management for the plans, minimums and maximums have been set for each of the asset classes listed above. All investment managers for the plan are subject to certain restrictions on the securities they purchase and, with the exception of indexing purposes, are prohibited from owning our stock.
The following tables set forth our pension benefits and postretirement benefits plan assets by fair value category as of the measurement date:
		Pension Benefits
		31-Dec-13
Asset Category		Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
Investments:
Equity securities (a)		$	680,590		$	60,336		$	—		$	740,926
Government obligations		—			111,288			—			111,288
Corporate obligations (b)		—			95,432			—			95,432
Cash and money market funds (c)		27,699			—			—			27,699
Insurance and group annuity contracts		—			—			63,458			63,458
Other investments (d)		—			—			73,946			73,946
Total assets		$	708,289		$	267,056		$	137,404		$	1,112,749
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category is primarily money market funds.
(d) - This category represents alternative investments.
		Pension Benefits
		31-Dec-12
Asset Category		Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
Investments:
Equity securities (a)		$	541,539		$	61,242		$	—		$	602,781
Government obligations		—			116,936			—			116,936
Corporate obligations (b)		—			104,078			—			104,078
Cash and money market funds (c)		33,296			—			—			33,296
Insurance and group annuity contracts		—			—			70,411			70,411
Other investments (d)		—			—			67,762			67,762
Total assets		$	574,835		$	282,256		$	138,173		$	995,264
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category is primarily money market funds.
(d) - This category represents alternative investments.
		Postretirement Benefits
		31-Dec-13
Asset Category		Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
Investments:
Equity securities (a)		$	37,796		$	90		$	—		$	37,886
Government obligations		—			166			—			166
Corporate obligations (b)		17,207			142			—			17,349
Cash and money market funds (c)		13,936			—			—			13,936
Insurance and group annuity contracts		—			106,189			—			106,189
Other investments (d)		—			—			109			109
Total assets		$	68,939		$	106,587		$	109		$	175,635
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category is primarily money market funds.
(d) - This category represents alternative investments.
		Postretirement Benefits
		31-Dec-12
Asset Category		Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
Investments:
Equity securities (a)		$	21,548		$	140		$	—		$	21,688
Government obligations		—			268			—			268
Corporate obligations (b)		17,522			238			—			17,760
Cash and money market funds (c)		18,311			—			—			18,311
Insurance and group annuity contracts		—			89,979			—			89,979
Other investments (d)		—			—			156			156
Total assets		$	57,381		$	90,625		$	156		$	148,162
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category represents money market funds.
(d) - This category represents alternative investments.
The following tables set forth the reconciliation of Level 3 fair value measurements of our pension plan for the periods indicated:
		Pension Benefits
		31-Dec-13
		Insurance			Other			Total
		and Group			Investments
		Annuity
		Contracts
		(Thousands of dollars)
1-Jan-13		$	70,411		$	67,762		$	138,173
Net realized and unrealized gains (losses)		(6,953		)	6,184			(769		)
31-Dec-13		$	63,458		$	73,946		$	137,404
		Pension Benefits
		31-Dec-12
		Insurance			Other			Total
		and Group			Investments
		Annuity
		Contracts
		(Thousands of dollars)
1-Jan-12		$	70,818		$	66,243		$	137,061
Net realized and unrealized gains (losses)		(407		)	1,519			1,112
31-Dec-12		$	70,411		$	67,762		$	138,173
Contributions - During 2013, we made no contributions to our defined benefit pension plans and $11.8 million in contributions to our postretirement benefit plans.  The contributions to our postretirement benefit plans were attributable to the 2014 plan year.  At December 31, 2013, we expect to make no contributions to our defined benefit pension plans and postretirement plans in 2014.
Pension and Postretirement Benefit Payments - Benefit payments for our pension and postretirement benefit plans for the period ending December 31, 2013, were $59.0 million and $18.4 million, respectively.  The following table sets forth the pension benefits and postretirement benefits payments expected to be paid in 2014-2023:
		Pension			Postretirement
		Benefits			Benefits
Benefits to be paid in:		(Thousands of dollars)
2014		$	63,856		$	16,251
2015		$	64,588		$	17,135
2016		$	66,477		$	18,142
2017		$	68,626		$	19,095
2018		$	70,873		$	19,875
2019 through 2023		$	386,366		$	106,346
The expected benefits to be paid are based on the same assumptions used to measure our benefit obligation at December 31, 2013, and include estimated future employee service.
Other Employee Benefit Plans
Thrift Plan - We have a Thrift Plan covering all full-time employees, and employee contributions are discretionary.  We match 100 percent of employee contributions up to 6 percent of each participant’s eligible compensation, subject to certain limits. Our contributions made to the plan were $17.0 million, $16.4 million and $15.9 million in 2013, 2012 and 2011, respectively.
Profit-Sharing Plan - We have a profit-sharing plan (Profit-Sharing Plan) for all nonbargaining unit employees hired after December 31, 2004, and employees covered by the IBEW collective bargaining agreement hired after June 30, 2010.  Nonbargaining unit employees who were employed prior to January 1, 2005, and employees covered by the IBEW collective bargaining agreement employed prior to July 1, 2010, were given a one-time opportunity to make an irrevocable election to participate in the Profit-Sharing Plan and not accrue any additional benefits under our defined benefit pension plan after December 31, 2004, and June 30, 2010, respectively.  Employees covered by the United Steelworker collective bargaining agreement employed prior to December 16, 2011, were given a one-time opportunity to make an irrevocable election to participate in the Profit-Sharing Plan.  We plan to make a contribution to the Profit-Sharing Plan each quarter equal to 1 percent of each participant’s eligible compensation during the quarter.  Additional discretionary employer contributions may be made at the end of each year.  Employee contributions are not allowed under the plan.  Our contributions made to the plan were $5.1 million, $6.6 million and $6.7 million in 2013, 2012 and 2011, respectively.
Employee Deferred Compensation Plan - The ONEOK, Inc. 2005 Nonqualified Deferred Compensation Plan provides select employees, as approved by our Board of Directors, with the option to defer portions of their compensation and provides nonqualified deferred compensation benefits that are not available due to limitations on employer and employee contributions to qualified defined contribution plans under the federal tax laws.  Our contributions made to the plan were not material in 2013, 2012 and 2011.
ONE Gas Employee Benefit Plans
In connection with the separation of the natural gas distribution business, ONEOK entered into an Employee Matters Agreement with ONE Gas, which provides that employees of ONE Gas no longer participate in benefit plans sponsored or maintained by ONEOK as of January 1, 2014. The ONEOK defined benefit pension plans and postretirement benefit plans transferred an allocable portion of assets and obligations related to those employees transferring to ONE Gas to newly established trusts for the ONE Gas plans. This resulted in a decrease in ONEOK’s sponsored qualified and nonqualified pension and postretirement plan obligations of approximately $1.1 billion and a decrease in ONEOK’s sponsored pension and postretirement plan assets of approximately $1.0 billion. Additionally, as a result of the transfer of unrecognized losses to ONE Gas, ONEOK’s deferred income taxes and regulatory assets decreased approximately $86.0 million and $331.1 million, respectively.

INCOME_TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
INCOME TAXES	'
	O.	INCOME TAXES
	The following table sets forth our provisions for income taxes for the periods indicated:
			Years Ended December 31,
			2013			2012			2011
	Current income taxes		(Thousands of dollars)
	Federal		$	7,313		$	(16,083	)	$	(32,291	)
	State		4,554			1,798			1,707
	Total current income taxes from continuing operations		11,867			(14,285		)	(30,584		)	(a)
	Deferred income taxes
	Federal		137,654			213,127			228,257
	State		13,861			16,353			28,375
	Total deferred income taxes from continuing operations		151,515			229,480			256,632			(a)
	Total provision for income taxes from continuing operations		163,382			215,195			226,048
	Discontinued operations		—			8,749			1,255
	Total provision for income taxes		$	163,382		$	223,944		$	227,303
	(a) Includes a $37.7 million reclassification from current income taxes to deferred related to revisions of estimated depreciation in our filed tax returns compared with our 2010 tax provision.
	The following table is a reconciliation of our income tax provision from continuing operations for the periods indicated:
			Years Ended December 31,
			2013			2012			2011
			(Thousands of dollars)
	Income from continuing operations before income taxes		$	740,343		$	944,446		$	983,562
	Less: Net income attributable to noncontrolling interest		310,428			382,911			399,150
	Income from continuing operations attributable to ONEOK before		429,915			561,535			584,412
	income taxes
	Federal statutory income tax rate		35		%	35		%	35		%
	Provision for federal income taxes		150,470			196,537			204,543
	State income taxes, net of federal tax benefit		11,970			11,799			20,334
	Other, net		942			6,859			1,171
	Income tax provision from continuing operations		$	163,382		$	215,195		$	226,048
	The following table sets forth the tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities for the periods indicated:
			December 31,			December 31,
			2013			2012
	Deferred tax assets		(Thousands of dollars)
	Employee benefits and other accrued liabilities		$	78,793		$	128,418
	Federal net operating loss		12,484			—
	State net operating loss and benefits		38,322			31,990
	Energy Services capacity release		46,726			—
	Other comprehensive income		78,369			140,802
	Other		20,872			1,446
	Total deferred tax assets		275,566			302,656
	Deferred tax liabilities
	Excess of tax over book depreciation and depletion		822,706			760,211
	Investment in partnerships		1,217,605			969,347
	Regulatory assets		132,676			204,625
	Total deferred tax liabilities		2,172,987			1,934,183
	Net deferred tax liabilities		$	1,897,421		$	1,631,527
	We had income taxes receivable of approximately $15.6 million and $30.8 million at December 31, 2013 and 2012, respectively.
	Tax benefits related to net operating loss (NOL) carryforwards will begin expiring in 2032. We believe that it is more likely than not that the tax benefits of the net operating loss carryforwards will be utilized prior to their expirations; therefore, no valuation allowance is necessary.
	Deferred tax assets related to tax benefits of employee share-based compensation have been reduced for performance share units and restricted share units that vested in periods in which ONEOK was in an NOL position.  This vesting resulted in tax deductions in excess of previously recorded benefits based on the performance share unit and restricted share unit value at the time of grant.  Although these additional tax benefits are reflected in NOL carryforwards in the tax return, the additional tax benefit is not recognized until the deduction reduces taxes payable.  A portion of the tax benefit does not reduce ONEOK’s current taxes payable due to NOL carryforwards; accordingly, these tax benefits are not reflected in ONEOK’s NOLs in deferred tax assets.  Tax benefits included in NOL carryforwards but not reflected in deferred tax assets were $35.9 million as of December 31, 2013, and $11.0 million as of December 31, 2012.

UNCONSOLIDATED_AFFILIATES

UNCONSOLIDATED AFFILIATES	12 Months Ended
	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]	'
UNCONSOLIDATED AFFILIATES	'
	P.	UNCONSOLIDATED AFFILIATES
	Investments in Unconsolidated Affiliates - The following table sets forth our investments in unconsolidated affiliates for the periods indicated:
			Net		December 31,				December 31,
			Ownership		2013				2012
			Interest
					(Thousands of dollars)
	Northern Border Pipeline		50%		$	404,803			$	393,317
	Overland Pass Pipeline Company		50%		466,671				468,710
	Fort Union Gas Gathering, L.L.C.		37%		125,220				120,782
	Bighorn Gas Gathering		49%		87,837				90,428
	Other		Various		145,307				148,168
	Investments in unconsolidated affiliates (a)				$	1,229,838			$	1,221,405
	(a) - Equity method goodwill (Note A) was $224.3 million at December 31, 2013 and 2012.
	Equity Earnings from Investments - The following table sets forth our equity earnings from investments for the periods indicated.  All amounts in the table below are equity earnings from investments in our ONEOK Partners segment:
			Years Ended December 31,
			2013				2012				2011
			(Thousands of dollars)
	Northern Border Pipeline		$	65,046			$	72,705			$	76,365
	Overland Pass Pipeline Company		20,461				20,043				19,535
	Fort Union Gas Gathering, L.L.C.		15,826				17,218				15,280
	Bighorn Gas Gathering		1,952				3,820				5,990
	Other		7,232				9,238				10,076
	Equity earnings from investments		$	110,517			$	123,024			$	127,246
	Unconsolidated Affiliates Financial Information - The following tables set forth summarized combined financial information of our unconsolidated affiliates for the periods indicated:
			December 31,				December 31,
			2013				2012
			(Thousands of dollars)
	Balance Sheet
	Current assets		$	155,310			$	175,930
	Property, plant and equipment, net		$	2,557,571			$	2,593,122
	Other noncurrent assets		$	34,478			$	35,005
	Current liabilities		$	98,967			$	145,147
	Long-term debt		$	442,103			$	472,630
	Other noncurrent liabilities		$	58,221			$	42,451
	Accumulated other comprehensive loss		$	(2,291	)		$	(2,503	)
	Owners’ equity		$	2,150,359			$	2,146,332
			Years Ended December 31,
			2013				2012				2011
			(Thousands of dollars)
	Income Statement
	Operating revenues		$	528,665			$	573,197			$	496,158
	Costs and expenses		$	256,292			$	269,858			$	221,261
	Net income		$	248,998			$	279,766			$	249,559
	Distributions paid to us		$	137,498			$	155,741			$	156,385
	We incurred expenses in transactions with unconsolidated affiliates of $53.8 million, $36.5 million, and $33.7 million for 2013, 2012, and 2011, respectively, primarily related to Overland Pass Pipeline Company. Accounts payable to our equity method investees at December 31, 2013 and 2012, were not material.
	Overland Pass Pipeline Company - The Overland Pass Pipeline Company limited liability company agreement provides that distributions to Overland Pass Pipeline Company’s members are to be made on a pro-rata basis according to each member’s percentage interest.  The Overland Pass Pipeline Company Management Committee determines the amount and timing of such distributions.  Any changes to, or suspensions of, cash distributions from Overland Pass Pipeline Company requires the unanimous approval of the Overland Pass Pipeline Management Committee.  Cash distributions are equal to 100 percent of available cash as defined in the limited liability company agreement.
	Northern Border Pipeline - The Northern Border Pipeline partnership agreement provides that distributions to Northern Border Pipeline’s partners are to be made on a pro-rata basis according to each partner’s percentage interest.  The Northern Border Pipeline Management Committee determines the amount and timing of such distributions.  Any changes to, or suspension of, the cash distribution policy of Northern Border Pipeline requires the unanimous approval of the Northern Border Pipeline Management Committee.  Cash distributions are equal to 100 percent of distributable cash flow as determined from Northern Border Pipeline’s financial statements based upon EBITDA, less interest expense and maintenance capital expenditures.  Loans or other advances from Northern Border Pipeline to its partners or affiliates are prohibited under its credit agreement.
	During 2013, ONEOK Partners made equity contributions to Northern Border Pipeline Company of approximately $30.8 million.
	In September 2012, Northern Border Pipeline filed with the FERC a settlement with its customers to modify its transportation rates. In January 2013, the settlement was approved and the new rates are effective January 1, 2013. The new long-term transportation rates are approximately 11 percent lower compared with previous rates.

ONEOK_PARTNERS

ONEOK PARTNERS	12 Months Ended
	Dec. 31, 2013
Related Party Transactions [Abstract]	'
ONEOK PARTNERS	'
	Q.	ONEOK PARTNERS
	Ownership Interest in ONEOK Partners - Our ownership interest in ONEOK Partners is shown in the table below as of December 31, 2013:
	General partner interest		2	%
	Limited partner interest (a)		39.2	%
	Total ownership interest		41.2	%
	(a) - Represents 19.8 million common units and approximately 73.0 million Class B units, which are convertible, at our option, into common units.
	Equity Issuances - In August 2013, ONEOK Partners completed an underwritten public offering of 11.5 million common units at a public offering price of $49.61 per common unit, generating net proceeds of approximately $553.3 million. In conjunction with this issuance, ONEOK Partners GP contributed approximately $11.6 million in order to maintain its 2 percent general partner interest in ONEOK Partners. ONEOK Partners used a portion of the proceeds from its August 2013 equity issuance to repay amounts outstanding under its commercial paper program and the balance was used for general partnership purposes.
	ONEOK Partners has an “at-the-market” equity program for the offer and sale from time to time of its common units up to an aggregate amount of $300 million. The program allows ONEOK Partners to offer and sell its common units at prices it deems appropriate through a sales agent. Sales of common units are made by means of ordinary brokers’ transactions on the NYSE, in block transactions, or as otherwise agreed to between ONEOK Partners and the sales agent. ONEOK Partners is under no obligation to offer and sell common units under the program. During the year ended December 31, 2013, ONEOK Partners sold 681 thousand common units through this program that resulted in net proceeds, including ONEOK Partners GP’s contribution to maintain its 2 percent general partner interest in ONEOK Partners, of approximately $36.1 million. ONEOK Partners used the proceeds for general partnership purposes.
	As a result of these transactions, ONEOK’s aggregate ownership interest in ONEOK Partners decreased to 41.2 percent at December 31, 2013, from 43.4 percent at December 31, 2012.
	In March 2012, ONEOK Partners completed an underwritten public offering of 8.0 million common units at a public offering price of $59.27 per common unit, generating net proceeds of approximately $460 million.  ONEOK Partners also sold 8.0 million common units to us in a private placement, generating net proceeds of approximately $460 million.  In conjunction with the issuances, ONEOK Partners GP contributed approximately $19 million in order to maintain its 2 percent general partner interest in ONEOK Partners.  ONEOK Partners used the net proceeds from the issuances to repay $295 million of borrowings under its commercial paper program, to repay amounts on the maturity of its $350 million, 5.9 percent senior notes due April 2012 and for other general partnership purposes, including capital expenditures.  As a result of these transactions, our aggregate ownership interest in ONEOK Partners increased to 43.4 percent at December 31, 2012, from 42.8 percent at December 31, 2011.
	We account for the difference between the carrying amount of our investment in ONEOK Partners and the underlying book value arising from issuance of common units by ONEOK Partners as an equity transaction.  If ONEOK Partners issues common units at a price different than our carrying value per unit, we account for the premium or deficiency as an adjustment to paid-in capital.  As a result of ONEOK Partners’ issuance of common units, we recognized an increase to paid-in capital of approximately $87.3 million, net of taxes, in 2013 and a decrease to paid-in capital of approximately $51.1 million, net of taxes, in 2012.
	Cash Distributions - We receive distributions from ONEOK Partners on our common and Class B units and our 2 percent general partner interest, which includes our incentive distribution rights.  Under ONEOK Partners’ partnership agreement, as amended, distributions are made to the partners with respect to each calendar quarter in an amount equal to 100 percent of available cash as defined in the ONEOK Partners partnership agreement (Partnership Agreement), as amended.  Available cash generally will be distributed 98 percent to limited partners and 2 percent to the general partner.  The general partner’s percentage interest in quarterly distributions is increased after certain specified target levels are met during the quarter.  In July 2011, the Partnership Agreement was amended to adjust the formula for distributing available cash among the general partner and limited partners to reflect the two-for-one unit split of ONEOK Partners’ common units.  Under the incentive distribution provisions, as set forth in ONEOK Partners’ partnership agreement, as amended, the general partner receives:
	•	15 percent of amounts distributed in excess of $0.3025 per unit;
	•	25 percent of amounts distributed in excess of $0.3575 per unit; and
	•	50 percent of amounts distributed in excess of $0.4675 per unit.
	The following table shows ONEOK Partners’ distributions paid during the periods indicated:
			Years Ended December 31,
			2013			2012		2011
			(Thousands, except per unit amounts)
	Distribution per unit		$	2.87		$	2.59	$	2.325
	General partner distributions		$	18,193		$	15,217	$	12,189
	Incentive distributions		251,664			186,130		123,386
	Distributions to general partner		269,857			201,347		135,575
	Limited partner distributions to ONEOK		266,302			235,442		197,132
	Limited partner distributions to noncontrolling interest		373,554			324,123		276,739
	Total distributions paid		$	909,713		$	760,912	$	609,446
	ONEOK Partners’ distributions are declared and paid within 45 days of the end of each quarter. The following table shows ONEOK Partners’ distributions declared for the periods indicated:
			Years Ended December 31,
			2013			2012		2011
			(Thousands, except per unit amounts)
	Distribution per unit		$	2.89		$	2.69	$	2.365
	General partner distributions		$	18,625		$	16,355	$	12,515
	Incentive distributions		259,466			210,095		131,212
	Distributions to general partner		278,091			226,450		143,727
	Limited partner distributions to ONEOK		268,157			249,600		200,524
	Limited partner distributions to noncontrolling interest		384,988			341,704		281,500
	Total distributions declared		$	931,236		$	817,754	$	625,751
	Acquisitions - On September 30, 2013, ONEOK Partners completed the Sage Creek acquisition for $305 million comprised of natural gas gathering and processing, and natural gas liquids facilities in Converse and Campbell counties, Wyoming, in the NGL-rich Niobrara Shale formation of the Powder River Basin. The Sage Creek acquisition consists primarily of a 50 MMcf/d natural gas processing facility, the Sage Creek plant, and related natural gas gathering and natural gas liquids infrastructure. Included in the acquisition were supply contracts providing for long-term acreage dedications from producers in the area, which are structured with POP and fee-based contractual terms. The acquisition is complementary to ONEOK Partners’ existing natural gas liquids assets and provides additional natural gas gathering and processing and natural gas liquids gathering capacity in a region where producers are actively drilling for crude oil and NGL-rich natural gas.
	ONEOK Partners accounted for this acquisition as a business combination, which, among other things, requires assets acquired and liabilities assumed to be measured at their acquisition-date fair values. The excess of the purchase price over the fair values of the identifiable assets acquired was recorded as goodwill.
	The purchase price and assessment of the fair value of the assets acquired and liabilities assumed were as follows (in thousands):
				Total
	Property, plant and equipment
	Gathering pipelines and related equipment			$	59,174
	Processing and fractionation and related equipment			50,595
	General plant and other			120
	Intangible assets			103,000
	Identifiable assets acquired			212,889
	Goodwill			92,000
	Total purchase price			$	304,889
	Identifiable intangible assets recognized in the Sage Creek acquisition are primarily related to natural gas gathering and processing and natural gas liquids supply contracts and customer relationships. The basis for determining the value of these intangible assets is the estimated future net cash flows to be derived from acquired supply contracts and customer relationships, which are offset with appropriate charges for the use of contributory assets and discounted using a risk-adjusted discount rate. Those intangible assets are being amortized on a straight-line basis over a period ranging from 20 to 30 years, which represents the periods during which the customer contracts and relationships are expected to contribute to ONEOK Partners’ cash flows.
	Revenues and earnings related to the Sage Creek acquisition are included within ONEOK Partners’ Consolidated Statement of Comprehensive Income since the acquisition dates. Supplemental pro forma revenue and earnings reflecting this acquisition as if it had occurred as of January 1, 2013, are not materially different from the information presented in ONEOK Partners’ accompanying Consolidated Statement of Comprehensive Income since the historical operations of this acquisition were insignificant relative to ONEOK Partners’ historical operations and are, therefore, not presented.
	In December 2013, ONEOK Partners acquired the remaining 30 percent undivided interest in its Maysville natural gas processing facility for $90 million. Beginning December 1, 2013, the results of operations for its 100 percent interest are included in our ONEOK Partners segment.
	Relationship - We consolidate ONEOK Partners in our consolidated financial statements; however, we are restricted from the assets and cash flows of ONEOK Partners except for the distributions we receive.  Distributions are declared quarterly by ONEOK Partners’ general partner based on the terms of the ONEOK Partners partnership agreement.  See Note S for more information on ONEOK Partners’ results.
	Affiliate Transactions - We have certain transactions with ONEOK Partners and its subsidiaries, which collectively comprise our ONEOK Partners segment.
	ONEOK Partners sells natural gas from its natural gas gathering and processing operations to our Energy Services segment.  In addition, a portion of ONEOK Partners’ revenues from its natural gas pipelines business is from our Energy Services and Natural Gas Distribution segments, which contract with ONEOK Partners for natural gas transportation and storage services. ONEOK Partners also purchases natural gas from our Energy Services segment for its natural gas liquids and its natural gas gathering and processing operations. As a result of the wind down activities discussed in Note B, our Energy Services segment will not execute affiliate transactions with ONEOK Partners after the wind down is completed. ONEOK Partners expects to continue providing midstream services, including marketing natural gas, NGLs and condensate as a service for third parties or other ONEOK affiliates. ONEOK Partners expects to enter into future commodity derivative financial contracts with unaffiliated third parties or ONEOK affiliates.
	Previously, ONEOK Partners had a Processing and Services Agreement with us and OBPI, under which it contracted for all of OBPI’s rights, including all of the capacity of the Bushton Plant, reimbursing OBPI for all costs associated with the operation and maintenance of the Bushton Plant and its obligations under equipment leases covering portions of the Bushton Plant. In June 2011, through a series of transactions, we sold OBPI to ONEOK Partners and OBPI closed the purchase option and terminated the equipment leases.  The total amount paid by ONEOK Partners to complete the transactions was approximately $94.2 million, which included the reimbursement to us of obligations related to the Processing and Services Agreement.
	We provide a variety of services to our affiliates, including cash management and financial services, legal and administrative services by our employees and management, insurance and office space leased in our headquarters building and other field locations.  Where costs are incurred specifically on behalf of an affiliate, the costs are billed directly to the affiliate by us.  In other situations, the costs may be allocated to the affiliates through a variety of methods, depending upon the nature of the expenses and the activities of the affiliates.  For example, a service that applies equally to all employees is allocated based upon the number of employees in each affiliate.  However, an expense benefiting the consolidated company but having no direct basis for allocation is allocated by the modified Distrigas method, a method using a combination of ratios that include gross plant and investment, operating income and payroll expense.  It is not practicable to determine what these general overhead costs would be on a stand-alone basis.
	The following table shows ONEOK Partners’ transactions with us for the periods indicated:
			Years Ended December 31,
			2013			2012		2011
			(Thousands of dollars)
	Revenues		$	340,743		$	352,099	$	403,603
	Expenses
Cost of sales and fuel		$	37,963		$	33,094	$	48,163
Administrative and general expenses		265,448			246,050		251,239
Total expenses		$	303,411		$	279,144	$	299,402

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
COMMITMENTS AND CONTINGENCIES	'
	R.	COMMITMENTS AND CONTINGENCIES
	Commitments - Operating leases represent future minimum lease payments under noncancelable equipment leases covering office space, pipeline equipment, rights of way and vehicles.  Firm transportation and storage contracts are fixed-price contracts that provide us with firm transportation and storage capacity.  Rental expense in 2013, 2012 and 2011 was not material.  The following table sets forth our operating lease and firm transportation and storage contract payments for the periods indicated:
	ONEOK		Operating
			Leases
			(Millions of dollars)
	2014		$	3.4
	2015		2.9
	2016		2.5
	2017		2.1
	2018		1.9
	Thereafter		3.3
	Total		$	16.1
	Our former Natural Gas Distribution segment is a party to fixed-price contracts providing it with firm transportation and storage capacity. The costs associated with these contracts are recovered through rates. Future commitments related to these contracts are $900.0 million. These contracts are obligations of ONE Gas as the result of the separation.
	Our Energy Services segment also is a party to fixed-price contracts related to firm transportation and storage that are not being released as part of the wind down process and will expire before April 2014. Future commitments related to these contracts are $11.2 million.
	ONEOK		Operating		Firm		Total
	Partners		Leases		Transportation
					and Storage
					Contracts
			(Millions of dollars)
	2014		$	2	$	18.4	$	20.4
	2015		0.5		16.3		16.8
	2016		0.3		14.4		14.7
	2017		0.2		12.8		13
	2018		0.2		11.9		12.1
	Thereafter		0.7		30.2		30.9
	Total		$	3.9	$	104	$	107.9
	Environmental Matters - We are subject to multiple historical preservation, wildlife preservation and environmental laws and/or regulations that affect many aspects of our present and future operations.  Regulated activities include, but are not limited to, those involving air emissions, storm water and wastewater discharges, handling and disposal of solid and hazardous wastes, wetland preservation, hazardous materials transportation, and pipeline and facility construction.  These laws and regulations require us to obtain and/or comply with a wide variety of environmental clearances, registrations, licenses, permits and other approvals.  Failure to comply with these laws, regulations, licenses and permits may expose us to fines, penalties and/or interruptions in our operations that could be material to our results of operations.  For example, if a leak or spill of hazardous substances or petroleum products occurs from pipelines or facilities that we own, operate or otherwise use, we could be held jointly and severally liable for all resulting liabilities, including response, investigation and cleanup costs, which could affect materially our results of operations and cash flows.  In addition, emissions controls and/or other regulatory or permitting mandates under the Clean Air Act and other similar federal and state laws could require unexpected capital expenditures at our facilities.  We cannot assure that existing environmental statutes and regulations will not be revised or that new regulations will not be adopted or become applicable to us.
	In June 2013, the Executive Office of the President of the United States issued the President’s Climate Action Plan, which includes, among other things, plans for further regulatory actions to reduce carbon emissions from various sources. The impact of any such regulatory actions on our facilities and operations is unknown. Revised or additional statutes or regulations that result in increased compliance costs or additional operating restrictions could have a significant impact on our business, financial position, results of operations and cash flows.
	We own or retain legal responsibility for the environmental conditions at 12 former manufactured natural gas sites in Kansas. The legal responsibility for these sites transferred to ONE Gas upon the separation. These sites contain potentially harmful materials that are subject to control or remediation under various environmental laws and regulations. A consent agreement with KDHE presently governs all work at these sites. The terms of the consent agreement allow us to investigate these sites and set remediation activities based upon the results of the investigations and risk analysis. Remediation typically involves the management of contaminated soils and may involve removal of structures and monitoring and/or remediation of groundwater.
	Of the 12 sites, we began soil remediation on 11 sites.  Regulatory closure has been achieved at three locations, and we completed or were near completion of soil remediation at eight sites.  We began site assessment at the remaining site where no active remediation has occurred.
	Our expenditures for environmental assessment, mitigation, remediation and compliance to date have not been significant in relation to our financial position, results of operations or cash flows, and our expenditures related to environmental matters have had no material effects on earnings or cash flows during 2013, 2012 or 2011.
	The EPA’s “Tailoring Rule” regulates greenhouse gas emissions at new or modified facilities that meet certain criteria. Affected facilities are required to review best available control technology, conduct air-quality and impact analyses and public reviews with respect to such emissions.  At current emissions threshold levels, this rule has had a minimal impact on our existing facilities.  The EPA has stated it will consider lowering the threshold levels over the next five years, which could increase the impact on our existing facilities; however, potential costs, fees or expenses associated with the potential adjustments are unknown.
	The EPA’s rule on air-quality standards, titled “National Emissions Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines,” also known as RICE NESHAP, initially included a compliance date in 2013.  Subsequent industry appeals and settlements with the EPA have extended timelines for compliance associated with the final RICE NESHAP rule. While the rule could require capital expenditures for the purchase and installation of new emissions-control equipment, we do not expect these expenditures will have a material impact on our results of operations, financial position or cash flows.
	In July 2011, the EPA issued a proposed rule that would change the air emissions New Source Performance Standards, also known as NSPS, and Maximum Achievable Control Technology requirements applicable to the oil and natural gas industry, including natural gas production, processing, transmission and underground storage sectors. In April 2012, the EPA released the final rule, which includes new NSPS and air toxic standards for a variety of sources within natural gas processing plants, oil and natural gas production facilities and natural gas transmission stations. The rule also regulates emissions from the hydraulic fracturing of wells for the first time. The EPA’s final rule reflects significant changes from the proposal issued in 2011 and allows for more manageable compliance options. The NSPS final rule became effective in October 2012, but the dates for compliance vary and depend in part upon the type of affected facility and the date of construction, reconstruction or modification.
	In March 2013, the EPA issued proposed rulemaking to amend the NSPS for the crude oil and natural gas industry, pursuant to various industry comments, administrative petitions for reconsideration and/or judicial appeals of portions of the NSPS final rule. The rule was most recently amended in September 2013, and the EPA has indicated that further amendments may be issued in 2014. Based on the amendments and our understanding of pending stakeholder responses to the NSPS rule, we anticipate a reduction in our anticipated capital, operations and maintenance costs resulting from compliance with the regulation. However, the EPA may issue additional responses, amendments and/or policy guidance on the final rule, which could alter our present expectations. Generally, the NSPS rule will require expenditures for updated emissions controls, monitoring and record-keeping requirements at affected facilities in the crude oil and natural gas industry. We do not expect these expenditures will have a material impact on our results of operations, financial position or cash flows.
	Pipeline Safety - We are subject to PHMSA regulations, including pipeline integrity-management regulations.  The Pipeline Safety Improvement Act of 2002 requires pipeline companies operating high-pressure pipelines to perform integrity assessments on pipeline segments that pass through densely populated areas or near specifically designated high-consequence areas.  In January 2012, The Pipeline Safety, Regulatory Certainty and Job Creation Act of 2011 was signed into law.  The law increased maximum penalties for violating federal pipeline safety regulations and directs the DOT and Secretary of Transportation to conduct further review or studies on issues that may or may not be material to us. These issues include but are not limited to the following:
	•	an evaluation on whether hazardous natural gas liquids and natural gas pipeline integrity-management requirements should be expanded beyond current high-consequence areas;
	•	a review of all natural gas and hazardous natural gas liquids gathering pipeline exemptions;
	•	a verification of records for pipelines in class 3 and 4 locations and high-consequence areas to confirm maximum allowable operating pressures; and
	•	a requirement to test previously untested pipelines operating above 30 percent yield strength in high-consequence areas.
	The potential capital and operating expenditures related to this legislation, the associated regulations or other new pipeline safety regulations are unknown.
	Financial Markets Legislation - The Dodd-Frank Act represents a far-reaching overhaul of the framework for regulation of United States financial markets. The CFTC has issued final regulations for most of the provisions of the Dodd-Frank Act, and we have implemented measures to comply with the regulations that are applicable to our businesses. ONEOK Partners continues to participate in financial markets for hedging certain risks inherent in its business, including commodity-price and interest-rate risks. Although the impact to date has not been material, ONEOK Partners continues to monitor proposed regulations and the impact these regulations may have on our business and risk-management strategies in the future.
	Legal Proceedings - Gas Index Pricing Litigation - As previously reported, ONEOK and its subsidiary, ONEOK Energy Services Company L.P. (OESC), along with several other energy companies, are defending multiple lawsuits arising from alleged market manipulation or false reporting of natural gas prices to natural gas-index publications. On April 10, 2013, the United States Court of Appeals for the Ninth Circuit reversed the summary judgments that had been granted in favor of ONEOK, OESC and other unaffiliated defendants in the following cases: Reorganized FLI, Learjet, Arandell, Heartland and NewPage. The Ninth Circuit also reversed the summary judgment that had been granted in favor of OESC on all state law claims asserted in the Sinclair case. The Ninth Circuit remanded the cases back to the United States District Court for the District of Nevada for further proceedings. ONEOK, OESC and the other unaffiliated defendants filed a Petition for Writ of Certiorari with the United States Supreme Court on August 26, 2013. The Ninth Circuit has ordered the cases stayed until the final disposition of the Petition for Writ of Certiorari.
	Because of the uncertainty surrounding the Gas Index Pricing Litigation, including an insufficient description of the purported classes and other related matters, we cannot reasonably estimate a range of potential exposures at this time. However, it is reasonably possible that the ultimate resolution of these matters could result in future charges that may be material to our results of operations.
	Other Legal Proceedings - We are a party to various other litigation matters and claims that have arisen in the normal course of our operations. While the results of these various other litigation matters and claims cannot be predicted with certainty, we believe the reasonably possible losses on 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.

SEGMENTS

SEGMENTS	12 Months Ended
	Dec. 31, 2013
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]	'
SEGMENTS	'
	S.	SEGMENTS
	Segment Descriptions - Our operations are divided into three reportable business segments as follows:
	•	our ONEOK Partners segment reflects the consolidated operations of ONEOK Partners.  At December 31, 2013, we have a 41.2 percent ownership interest and control ONEOK Partners through our ownership of its general partner interest.  ONEOK Partners gathers, processes, treats, transports, stores and sells natural gas and gathers, treats, fractionates, stores, distributes and markets NGLs.  We and ONEOK Partners maintain significant financial and corporate governance separations.  We seek to receive increasing cash distributions as a result of our investment in ONEOK Partners, and our investment decisions are made based on the anticipated returns from ONEOK Partners in total, not specific to any of its businesses individually;
	•	our former Natural Gas Distribution segment, which we separated into a standalone publicly traded company, ONE Gas, on January 31, 2014, was comprised of regulated public utilities that deliver natural gas to residential, commercial and industrial customers, and transport natural gas; and
	•	our Energy Services segment, which we are winding down, markets natural gas to wholesale customers.
	Other and eliminations consist of the operating and leasing operations of our headquarters building and related parking facility and other amounts needed to reconcile our reportable segments to our consolidated financial statements.
	Accounting Policies - We evaluate performance based principally on each segment’s operating income and equity earnings. The accounting policies of the segments are the same as those described in Note A.  Intersegment sales are recorded on the same basis as sales to unaffiliated customers and are discussed in further detail in Note Q.  Net margin is comprised of total revenues less cost of sales and fuel.  Cost of sales and fuel includes commodity purchases, fuel, and storage and transportation costs.
	Customers - In 2013, 2012 and 2011, we had no single external customer from which we received 10 percent or more of our consolidated gross revenues.
	Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated:
	Year Ended December 31, 2013		ONEOK			Natural Gas			Energy			Other and			Total
			Partners (a)			Distribution			Services			Eliminations
			(Thousands of dollars)
	Sales to unaffiliated customers		$	11,528,530		$	1,689,945		$	1,381,636		$	2,606		$	14,602,717
	Intersegment revenues		340,743			7			195,926			(536,676		)	—
	Total revenues		$	11,869,273		$	1,689,952		$	1,577,562		$	(534,070	)	$	14,602,717
	Net margin		$	1,647,060		$	813,008		$	(172,985	)	$	2,600		$	2,289,683
	Operating costs		521,513			444,866			13,133			10,941			990,453
	Depreciation and amortization		236,743			144,758			277			2,599			384,377
	Gain on sale of assets		11,881			—			—			—			11,881
	Operating income		$	900,685		$	223,384		$	(186,395	)	$	(10,940	)	$	926,734
	Equity earnings from investments		$	110,517		$	—		$	—		$	—		$	110,517
	Investments in unconsolidated affiliates		$	1,229,838		$	—		$	—		$	—		$	1,229,838
	Total assets		$	12,862,608		$	3,857,722		$	347,470		$	639,758		$	17,707,558
	Noncontrolling interests in consolidated subsidiaries		$	4,536		$	—		$	—		$	2,502,793		$	2,507,329
	Capital expenditures		$	1,939,326		$	292,080		$	—		$	25,179		$	2,256,585
	(a) - Our ONEOK Partners segment has regulated and nonregulated operations. Our ONEOK Partners segment’s regulated operations had
	revenues of $781.7 million, net margin of $545.0 million and operating income of $281.0 million.
	Year Ended December 31, 2012		ONEOK			Natural Gas			Energy			Other and			Total
			Partners (a)			Distribution			Services			Eliminations
			(Thousands of dollars)
	Sales to unaffiliated customers		$	9,830,052		$	1,379,366		$	1,421,171		$	1,970		$	12,632,559
	Intersegment revenues		352,099			(2,717		)	105,402			(454,784		)	—
	Total revenues		$	10,182,151		$	1,376,649		$	1,526,573		$	(452,814	)	$	12,632,559
	Net margin		$	1,641,832		$	756,389		$	(49,344	)	$	1,964		$	2,350,841
	Operating costs		482,540			410,572			17,950			(2,084		)	908,978
	Depreciation and amortization		203,101			130,150			361			2,232			335,844
	Goodwill impairment		—			—			10,255			—			10,255
	Gain on sale of assets		6,736			—			—			—			6,736
	Operating income		$	962,927		$	215,667		$	(77,910	)	$	1,816		$	1,102,500
	Equity earnings from investments		$	123,024		$	—		$	—		$	—		$	123,024
	Investments in unconsolidated affiliates		$	1,221,405		$	—		$	—		$	—		$	1,221,405
	Total assets		$	10,959,230		$	3,535,489		$	493,006		$	867,550		$	15,855,275
	Noncontrolling interests in consolidated subsidiaries		$	4,767		$	—		$	—		$	2,098,074		$	2,102,841
	Capital expenditures		$	1,560,513		$	280,294		$	—		$	25,346		$	1,866,153
	(a) - Our ONEOK Partners segment has regulated and non-regulated operations. Our ONEOK Partners segment’s regulated operations had
	revenues of $722.1 million, net margin of $618.0 million and operating income of $375.6 million.
	Year Ended December 31, 2011		ONEOK			Natural Gas			Energy			Other and			Total
			Partners (a)			Distribution			Services			Eliminations
			(Thousands of dollars)
	Sales to unaffiliated customers		$	10,919,004		$	1,609,628		$	2,274,799		$	2,363		$	14,805,794
	Intersegment revenues		403,603			11,706			502,418			(917,727		)	—
	Total revenues		$	11,322,607		$	1,621,334		$	2,777,217		$	(915,364	)	$	14,805,794
	Net margin		$	1,577,380		$	751,835		$	48,740		$	2,404		$	2,380,359
	Operating costs		459,364			422,073			24,527			2,359			908,323
	Depreciation and amortization		177,549			132,212			445			1,954			312,160
	Loss on sale of assets		(963		)	—			—			—			(963		)
	Operating income		939,504			197,550			23,768			(1,909		)	1,158,913
	Equity earnings from investments		$	127,246		$	—		$	—		$	—		$	127,246
	Investments in unconsolidated affiliates		$	1,223,398		$	—		$	—		$	—		$	1,223,398
	Total assets		$	8,946,676		$	3,392,475		$	562,728		$	794,756		$	13,696,635
	Noncontrolling interests in consolidated subsidiaries		$	5,112		$	—		$	—		$	1,556,047		$	1,561,159
	Capital expenditures		$	1,063,383		$	242,590		$	41		$	30,053		$	1,336,067
	(a) - Our ONEOK Partners segment has regulated and non-regulated operations. Our ONEOK Partners segment’s regulated operations had
revenues of $658.5 million, net margin of $469.0 million and operating income of $232.8 million.

QUARTERLY_FINANCIAL_DATA_UNAUD

QUARTERLY FINANCIAL DATA (UNAUDITED)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
QUARTERLY FINANCIAL DATA (UNAUDITED)	'
	T.	QUARTERLY FINANCIAL DATA (UNAUDITED)
			First		Second		Third		Fourth
	Year Ended December 31, 2013		Quarter		Quarter		Quarter		Quarter
			(Thousands of dollars except per share amounts)
	Total revenues		$	3,541,445	$	3,349,236	$	3,571,925	$	4,140,111
	Net margin		$	623,452	$	453,389	$	561,188	$	651,654
	Income from continuing operations		$	165,705	$	79,495	$	147,698	$	184,063
	Net income		$	165,705	$	79,495	$	147,698	$	184,063
	Net income attributable to ONEOK		$	112,521	$	919	$	62,356	$	90,737
	Earnings per share total
	Basic		$	0.55	$	—	$	0.3	$	0.44
	Diluted		$	0.54	$	—	$	0.3	$	0.43
			First		Second		Third		Fourth
	Year Ended December 31, 2012		Quarter		Quarter		Quarter		Quarter
			(Thousands of dollars except per share amounts)
	Total revenues		$	3,414,600	$	2,529,260	$	3,028,775	$	3,659,924
	Net margin		$	643,587	$	548,962	$	553,972	$	604,320
	Income from continuing operations		$	219,450	$	148,938	$	164,988	$	195,875
	Income from discontinued operations and gain on sale,		$	14,012	$	267	$	—	$	—
	net of tax
	Net income		$	233,462	$	149,205	$	164,988	$	195,875
	Net income attributable to ONEOK		$	122,865	$	60,993	$	65,219	$	111,542
	Earnings per share total
	Basic		$	0.59	$	0.29	$	0.32	$	0.55
	Diluted		$	0.58	$	0.29	$	0.31	$	0.53

SUBSEQUENT_EVENTS_Notes

SUBSEQUENT EVENTS (Notes)	3 Months Ended
	Mar. 31, 2014
Subsequent Event [Line Items]	'
Subsequent Events [Text Block]	'
	U.	Subsequent Events
	On January 8, 2014, our Board of Directors unanimously approved the distribution of all the shares of common stock of ONE Gas, our wholly owned subsidiary, to our shareholders. On January 14, 2014, we entered into the following agreements with ONE Gas which provide a framework for our relationship with ONE Gas after the distribution:
	•	Separation and Distribution Agreement - sets forth the agreements between us and ONE Gas regarding the principal transactions necessary to effect the distribution. This agreement also sets forth other agreements that govern certain aspects of our relationship with ONE Gas after the completion of the distribution.
	•	Tax Matters Agreement - governs the parties’ respective rights, responsibilities and obligations with respect to tax liabilities and benefits, tax attributes, the preparation and filing of tax returns, the control of audits and other tax proceedings and other matters regarding taxes.
	•	Transition Services Agreement - provides for an orderly transition to ONE Gas being an independent, publicly traded company. Under this agreement, ONEOK and ONE Gas have agreed to provide each other with various services, including services relating to treasury and risk management, human resources and payroll management, tax compliance, telecommunications services and information technology services.
	•	Employee Matters Agreement - allocates liabilities and responsibilities relating to employee compensation and benefit plans and programs and other related matters in connection with the separation, including the treatment of outstanding incentive awards and certain retirement and welfare benefit obligations.
	On January 27, 2014, ONE Gas, which at the time was our wholly owned subsidiary, completed a private placement of three series of Senior Notes totaling $1.2 billion. The following table details information about each of the three series of Senior Notes:
			(In millions)
	2.07% notes due February 1, 2019		$	300
	3.61% notes due February 1, 2024		300
	4.658% notes due February 1, 2044		600
			$	1,200
	Our obligations related to the ONE Gas Senior Notes and Credit Agreement terminated in connection with the completion of the separation of ONE Gas.
	ONE Gas made a cash payment to us of approximately $1.13 billion from the proceeds of this offering. In February 2014, we retired approximately $152.5 million of the 4.25 percent senior notes due 2022 through a tender offer. The total amount paid, including fees and other charges, was approximately $150 million. We also repaid all commercial paper outstanding, which totaled approximately $600.5 million.
	On January 31, 2014, the separation of ONE Gas was completed through a stock dividend distribution of ONE Gas shares to our shareholders after the market closed. We distributed one share of common stock of ONE Gas for every four shares of ONEOK common stock held by ONEOK shareholders of record as of the close of business on January 21, 2014, the record date for the distribution.  We retained no ownership interest in ONE Gas.
	In February 2014, we made an irrevocable election to exercise the make-whole call on our $400 million, 5.2 percent senior notes due in 2015. The full repayment is expected to occur in March 2014 and is estimated to be approximately $429 million, which includes accrued but unpaid interest to the redemption date.
	In connection with the separation, John W. Gibson retired as Chief Executive Officer of ONEOK and remained Chairman of the Board of ONEOK and ONEOK Partners, effective January 31, 2014. Our Board of Directors approved the expansion of the number of directors of the Board of Directors of ONEOK to 11 from 10 and elected Terry K. Spencer to serve as a member of the Board of Directors effective January 31, 2014. Mr. Spencer serves on the Executive Committee. Mr. Spencer also was elected President and Chief Executive Officer of ONEOK and ONEOK Partners. Also in connection with the separation, Pierce H. Norton II resigned as an officer of ONEOK effective January 31, 2014, to become President and Chief Executive Officer of ONE Gas.

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2013
Entity [Line Items]	'
Consolidation	'
	Consolidation - Our consolidated financial statements include the accounts of ONEOK and our subsidiaries over which we have control or are the primary beneficiary.  We have recorded noncontrolling interests in consolidated subsidiaries on our Consolidated Balance Sheets to recognize the portion of ONEOK Partners that we do not own.  We reflected our ownership interest in ONEOK Partners’ accumulated other comprehensive income (loss) in our consolidated accumulated other comprehensive income (loss).  The remaining portion is reflected as an adjustment to noncontrolling interests in consolidated subsidiaries.  All significant intercompany balances and transactions have been eliminated in consolidation. We have recast prior period amounts in the Consolidated Statements of Cash Flows to revise the classification of the excess tax benefit of share-based compensation to financing from operating activities.
	Investments in unconsolidated affiliates are accounted for using the equity method if we have the ability to exercise significant influence over operating and financial policies of our investee. Under this method, an investment is carried at its acquisition cost and adjusted each period for contributions made, distributions received and our share of the investee’s comprehensive income. For the investments we account for under the equity method, the premium or excess cost over underlying fair value of net assets is referred to as equity method goodwill. Impairment of equity investments is recorded when the impairments are other than temporary. These amounts are recorded as investments in unconsolidated affiliates on our accompanying Consolidated Balance Sheets. Distributions paid to us from our unconsolidated affiliates are classified as operating activities on our Consolidated Statements of Cash Flows until the cumulative distributions exceed our proportionate share of income from the unconsolidated affiliate since the date of our initial investment.  The amount of cumulative distributions paid to us that exceeds our cumulative proportionate share of income in each period represents a return of investment and is classified as an investing activity on our Consolidated Statements of Cash Flows. See Note P for disclosures of our unconsolidated affiliates.
Use of Estimates	'
	Use of Estimates - The preparation of our consolidated financial statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amount of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements.  These estimates and assumptions also affect the reported amounts of revenue and expenses during the reporting period.  Items that may be estimated include, but are not limited to, the economic useful life of assets, fair value of assets and liabilities, obligations under employee benefit plans, provisions for uncollectible accounts receivable, unbilled revenues for natural gas delivered but for which meters have not been read, gas purchased expense for natural gas purchased but for which no invoice has been received, provision for income taxes, including any deferred tax valuation allowances, the results of litigation and various other recorded or disclosed amounts.
	We evaluate these estimates on an ongoing basis using historical experience, consultation with experts and other methods we consider reasonable based on the particular circumstances.  Nevertheless, actual results may differ significantly from the estimates. Any effects on our financial position or results of operations from revisions to these estimates are recorded in the period when the facts that give rise to the revision become known.
Fair Value Measurements	'
	Fair Value Measurements - We define fair value as the price that would be received from the sale of an asset or the transfer of a liability in an orderly transaction between market participants at the measurement date.  We use the market and income approaches to determine the fair value of our assets and liabilities and consider the markets in which the transactions are executed. 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.
	While many of the contracts in our portfolio are executed in liquid markets where price transparency exists, some contracts are executed in markets for which market prices may exist, but the market may be relatively inactive.  This results in limited price transparency that requires management’s judgment and assumptions to estimate fair values.  Inputs into our fair value estimates include commodity-exchange prices, over-the-counter quotes, volatility, historical correlations of pricing data and LIBOR and other liquid money-market instrument rates.  We also utilize internally developed basis curves that incorporate observable and unobservable market data.  We validate our valuation inputs with third-party information and settlement prices from other sources, where available.
	In addition, as prescribed by the income approach, 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 LIBOR, Eurodollar futures and interest-rate swaps.  We also take into consideration the potential impact on market prices of liquidating positions in an orderly manner over a reasonable period of time under current market conditions.  We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using specific and sector bond yields and also monitor the credit default swap markets.  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 from our estimates, and the differences could be material.
	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.
	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 - Unadjusted quoted prices in active markets for identical assets or liabilities;
	•	Level 2 - Significant observable pricing inputs other than quoted prices included within Level 1 that are, either directly or indirectly, observable as of the reporting date.  Essentially, this represents inputs that are derived principally from or corroborated by observable market data; and
	•	Level 3 - May include one or more unobservable inputs that are significant in establishing a fair value estimate.  These unobservable inputs are developed based on the best information available and may include our own internal data.
	We recognize transfers into and out of Level 3 as of the end of each reporting period.  Transfers into Level 3 represent existing assets or liabilities that were categorized previously at a higher level for which the unobservable inputs became a more significant portion of the fair value estimates. Transfers out of Level 3 represent existing assets and liabilities that were classified previously as Level 3 for which the observable inputs became a more significant portion of the fair value estimates.
	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.  See Note D for additional disclosures of our fair value measurements.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents - Cash equivalents consist of highly liquid investments, which are readily convertible into cash and have original maturities of three months or less.
Revenue Recognition	'
	Revenue Recognition - Our operating segments recognize revenue when services are rendered or product is delivered. ONEOK Partners’ natural gas gathering and processing operations record revenue when gas is processed in or transported through its facilities.  ONEOK Partners’ natural gas liquids operations record revenues based upon contracted services and actual volumes exchanged or stored under service agreements in the period services are provided.  Revenue for ONEOK Partners’ natural gas pipelines and a portion of its natural gas liquids operations is recognized based upon contracted capacity and contracted volumes transported and stored under service agreements in the period services are provided.
	Our former Natural Gas Distribution segment’s major industrial and commercial natural gas distribution customers are invoiced at the end of each month.  All natural gas distribution residential customers and some commercial customers are invoiced on a cyclical basis throughout the month, and the utilities accrue unbilled revenues at the end of each month.
	Our revenues from sales to our Energy Services segment’s wholesale customers are accrued in the month of physical delivery based on contracted sales price and estimated volumes.  Demand payments received for requirements contracts are recognized in the period in which the service is provided.  Our fixed-price physical sales are accounted for as derivatives and are recorded at fair value.  See discussion below in “Derivative and Risk Management Activities” for additional information.
Accounts Receivable	'
	Accounts Receivable - Accounts receivable represent valid claims against nonaffiliated customers for products sold or services rendered, net of allowances for doubtful accounts.  We assess the creditworthiness of our counterparties on an ongoing basis and require security, including prepayments and other forms of collateral, when appropriate.  Outstanding customer receivables are reviewed regularly for possible nonpayment indicators and allowances for doubtful accounts are recorded based upon management’s estimate of collectability at each balance sheet date.  At December 31, 2013 and 2012, our allowance for doubtful accounts was not material.
Inventories	'
	Inventories - The values of current natural gas and NGLs in storage are determined using the lower of weighted-average cost or market method.  Noncurrent natural gas and NGLs are classified as property and valued at cost.  Materials and supplies are valued at average cost.
Commodity Imbalances	'
	Commodity Imbalances - Commodity imbalances represent amounts payable or receivable for NGL exchange contracts and natural gas pipeline imbalances and are valued at fair value.  Under the majority of our NGL exchange agreements, we physically receive volumes of unfractionated NGLs, including the risk of loss and legal title to such volumes, from the exchange counterparty.  In turn, we deliver NGL products back to the customer and charge them gathering and fractionation fees. To the extent that the volumes we receive under such agreements differ from those we deliver, we record a net exchange receivable or payable position with the counterparties.  These net exchange receivables and payables are settled with movements of NGL products rather than with cash.  Natural gas pipeline imbalances are settled in cash or in-kind, subject to the terms of the pipelines’ tariffs or by agreement.
Derivatives and Risk Management Activities	'
	Derivatives and Risk Management Activities - We record all derivative instruments at fair value, with the exception of normal purchases and normal sales that are expected to result in physical delivery.  The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and, if so, the reason for holding it.
	If certain conditions are met, we may elect to designate a derivative instrument as a hedge of exposure to changes in fair values, cash flows or foreign currency.  Certain nontrading derivative transactions, which are economic hedges of our accrual transactions such as our storage and transportation contracts, do not qualify for hedge accounting treatment.
	The table below summarizes the various ways in which we account for our derivative instruments and the impact on our consolidated financial statements:
			Recognition and Measurement
	Accounting Treatment		Balance Sheet		Income Statement
	Normal purchases and	-	Fair value not recorded	-	Change in fair value not recognized in earnings
	normal sales
	Mark-to-market	-	Recorded at fair value	-	Change in fair value recognized in earnings
	Cash flow hedge	-	Recorded at fair value	-	Ineffective portion of the gain or loss on the
					derivative instrument is recognized in earnings
		-	Effective portion of the gain or loss on the	-	Effective portion of the gain or loss on the
			derivative instrument is reported initially as a		derivative instrument is reclassified out of
			component of accumulated other		accumulated other comprehensive income (loss)
			comprehensive income (loss)		into earnings when the forecasted transaction
					affects earnings
	Fair value hedge	-	Recorded at fair value	-	The gain or loss on the derivative instrument is
					recognized in earnings
		-	Change in fair value of the hedged item is	-	Change in fair value of the hedged item is
			recorded as an adjustment to book value		recognized in earnings
	Gains or losses associated with the fair value of derivative instruments entered into by our Natural Gas Distribution segment are included in, and recoverable through, the monthly purchased-gas cost mechanism.
	We formally document all relationships between hedging instruments and hedged items, as well as risk-management objectives, strategies for undertaking various hedge transactions and methods for assessing and testing correlation and hedge ineffectiveness. We specifically identify the asset, liability, firm commitment or forecasted transaction that has been designated as the hedged item.  We assess the effectiveness of hedging relationships quarterly by performing an effectiveness analysis on our cash flow and fair value hedging relationships to determine whether the hedge relationships are highly effective on a retrospective and prospective basis.  We also document our normal purchases and normal sales transactions that we expect to result in physical delivery and that we elect to exempt from derivative accounting treatment.
	The presentation of settled derivative instruments on either a gross or net basis in our Consolidated Statements of Income is dependent on the relevant facts and circumstances of our different types of activities rather than based solely on the terms of the individual contracts.  All financially settled derivative instruments, as well as derivative instruments considered held for trading purposes that result in physical delivery, are reported on a net basis in revenues in our Consolidated Statements of Income.  The realized revenues and purchase costs of derivative instruments that are not considered held for trading purposes and nonderivative contracts are reported on a gross basis.  Derivatives that qualify as normal purchases or normal sales that are expected to result in physical delivery are also reported on a gross basis.
	Revenues in our Consolidated Statements of Income include financial trading margins, as well as certain physical natural gas transactions with our trading counterparties.  Revenues and cost of sales and fuel from such physical transactions are reported on a net basis.
	Cash flows from futures, forwards, options and swaps that are accounted for as hedges are included in the same category as the cash flows from the related hedged items in our Consolidated Statements of Cash Flows.
	See Notes D and E for more discussion of our fair value measurements and risk management and hedging activities using derivatives.
Property, Plant and Equipment	'
	Property, Plant and Equipment - Our properties are stated at cost, including AFUDC.  Generally, the cost of regulated property retired or sold, plus removal costs, less salvage, is charged to accumulated depreciation.  Gains and losses from sales or retirement of nonregulated properties or an entire operating unit or system of our regulated properties are recognized in income. Maintenance and repairs are charged directly to expense.
	The interest portion of AFUDC represents the cost of borrowed funds used to finance construction activities.  We capitalize interest costs during the construction or upgrade of qualifying assets. Capitalized interest is recorded as a reduction to interest expense. The equity portion of AFUDC represents the capitalization of the estimated average cost of equity used during the construction of major projects and is recorded in the cost of our regulated properties and as a credit to the allowance for equity funds used during construction.
	Our properties are depreciated using the straight-line method over their estimated useful lives.  Generally, we apply composite depreciation rates to functional groups of property having similar economic circumstances.  We periodically conduct depreciation studies to assess the economic lives of our assets.  For our regulated assets, these depreciation studies are completed as a part of our rate proceedings or tariff filings, and the changes in economic lives, if applicable, are implemented prospectively when the new rates are billed.  For our nonregulated assets, if it is determined that the estimated economic life changes, the changes are made prospectively.  Changes in the estimated economic lives of our property, plant and equipment could have a material effect on our financial position or results of operations.
	Property, plant and equipment on our Consolidated Balance Sheets includes construction work in process for capital projects that have not yet been placed in service and therefore are not being depreciated.  Assets are transferred out of construction work in process when they are substantially complete and ready for their intended use.
	See Note F for disclosures of our property, plant and equipment.
Impairment of Goodwill and Long-Lived Assets, including Intangible Assets	'
	Impairment of Goodwill and Long-Lived Assets, Including Intangible Assets - We assess our goodwill and indefinite-lived intangible assets for impairment at least annually as of July 1. Our goodwill impairment analysis performed as of July 1, 2013, did not result in an impairment charge nor did our analysis reflect any reporting units at risk, and subsequent to that date, no event has occurred indicating that the implied fair value of each of our reporting units (including its inherent goodwill) is less than the carrying value of its net assets.
	As a result of the decline in natural gas prices and its effect on location and seasonal price differentials, we performed an interim impairment assessment of our Energy Services segment’s goodwill balance as of March 31, 2012.  As a result of that assessment, goodwill with a carrying amount of $10.3 million was written down to its implied fair value of zero, with a resulting impairment charge of $10.3 million recorded in 2012 earnings. For the remaining segments, Natural Gas Distribution and ONEOK Partners, there were no impairment indicators as the cash flows generated from each of these segments are derived from predominately fee-based, nondiscretionary services. There were also no impairment charges resulting from our 2012 and 2011 annual impairment tests.
	As part of our goodwill impairment test, we first assess qualitative factors (including macroeconomic conditions, industry and market considerations, cost factors and overall financial performance) to determine whether it is more likely than not that the fair value of each of our reporting units is less than its carrying amount. If further testing is necessary, we perform a two-step impairment test for goodwill. In the first step, an initial assessment is made by comparing the fair value of a reporting unit with its book value, including goodwill.  If the fair value is less than the book value, an impairment is indicated, and we must perform a second test to measure the amount of the impairment.  In the second test, we calculate the implied fair value of the goodwill by deducting the fair value of all tangible and intangible net assets of the reporting unit from the fair value determined in step one of the assessment.  If the carrying value of the goodwill exceeds the implied fair value of the goodwill, we will record an impairment charge.
	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 multiples to forecasted cash flows.  The multiples used are consistent with historical asset transactions.  The forecasted cash flows are based on average forecasted cash flows over a period of years.
	As part of our indefinite-lived intangible asset impairment test, we first assess qualitative factors similar to those considered in the goodwill impairment test to determine whether it is more likely than not that the indefinite-lived intangible asset was impaired. If further testing is necessary, we compare the estimated fair value of our indefinite-lived intangible asset with its book value.  The fair value of our indefinite-lived intangible asset is estimated using the market approach. Under the market approach, we apply multiples to forecasted cash flows of the assets associated with our indefinite-lived intangible asset.  The multiples used are consistent with historical asset transactions.  After assessing qualitative factors, we determined that there were no impairments to our indefinite-lived intangible asset in 2013. There were also no impairment charges resulting from our 2012 and 2011 annual impairment tests.
	We assess our long-lived assets, including intangible assets with finite useful lives, 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 determined that there were no asset impairments in 2013, 2012 or 2011.
	For the investments we account for under the equity method, the impairment test 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 reevaluate the amount at which we carry our equity method investments to determine whether current events or circumstances warrant adjustments to our carrying value.  We determined that there were no impairments to our investments in unconsolidated affiliates in 2013, 2012 or 2011.
	Low natural gas prices and the relatively higher crude oil and NGL prices, compared with natural gas on a heating-value basis, have caused producers primarily to focus development efforts on crude oil and NGL-rich supply basins rather than areas with dry natural gas production, such as the coal-bed methane areas in the Powder River Basin.  The reduced coal-bed methane development activities and natural production declines in the dry natural gas formation of the Powder River Basin resulted in lower volumes available to be gathered.  While the reserve potential in the Powder River Basin still exists, future drilling and development will be affected by commodity prices and producers’ alternative prospects.  Bighorn Gas Gathering, in which ONEOK Partners owns a 49 percent equity interest, has operations in the coal-bed methane areas of the Powder River Basin. Due to declines in volumes gathered on Bighorn Gas Gathering’s system, ONEOK Partners tested its investment for impairment at December 31, 2013. The estimated fair value exceeded the carrying value; however, a decline of 10 percent or more in the fair value of ONEOK Partners’ investment in Bighorn Gas Gathering would result in a noncash impairment charge. ONEOK Partners was not able to estimate reasonably a range of potential future impairment charges, as many of the assumptions that would be used in its estimate of fair value are dependent upon events beyond its control. The carrying amount of ONEOK Partners’ investment as of December 31, 2013, was $87.8 million, which includes $53.4 million in equity method goodwill. ONEOK Partners estimated the fair value of its investment in Bighorn Gas Gathering using an income approach, which discounted the cash flows of ONEOK Partners investment’s underlying assets with a discount rate reflective of its cost of capital and estimated contract rates, volumes, operating and maintenance costs and capital expenditures.
	A continued decline in coal-bed methane natural gas volumes in the coal-bed methane production areas of the Powder River Basin may reduce ONEOK Partners’ ability to recover the carrying value of its assets and equity investments in this area and could result in noncash charges to earnings. For ONEOK Partners’ other equity method investments with operations in the Powder River Basin with carrying values of approximately $204 million, which includes approximately $130 million in equity method goodwill, ONEOK Partners did not identify current events or circumstances that warranted an impairment analysis or an adjustment to its carrying values. ONEOK Partners is not able to reasonably estimate a range of potential future charges, as many of the assumptions that would be used in a fair value model are dependent upon events such as commodity prices, producers’ drilling and production activity and effects of government regulations and policies.
	Our impairment tests require the use of assumptions and estimates such as industry economic factors and the profitability of future business strategies.  If actual results are not consistent with our assumptions and estimates or our assumptions and estimates change due to new information, we may be exposed to future impairment charges.
	See Notes F, G and P for our long-lived assets, goodwill and intangible assets and investment in unconsolidated affiliates disclosures.
Regulation	'
	Regulation - Our former natural gas distribution operations and ONEOK Partners’ intrastate natural gas transmission pipelines are subject to the rate regulation and accounting requirements of the OCC, KCC, RRC and various municipalities in Texas. ONEOK Partners’ interstate natural gas and natural gas liquids pipelines are subject to regulation by the FERC.  In Kansas and Texas, natural gas storage may be regulated by the state and the FERC for certain types of services.  Oklahoma Natural Gas, Kansas Gas Service, Texas Gas Service and portions of our ONEOK Partners segment follow the accounting and reporting guidance for regulated operations.  During the rate-making process, regulatory authorities set the framework for what we can charge customers for our services and establish the manner that our costs are accounted for, including allowing us to defer recognition of certain costs and permitting recovery of the amounts through rates over time, as opposed to expensing such costs as incurred. Examples include costs for fuel and fuel losses, acquisition costs and contributions in aid of construction. This allows us to stabilize rates over time rather than passing such costs on to the customer for immediate recovery.  Actions by regulatory authorities could have an effect on the amount recovered from rate payers.  Any difference in the amount recoverable and the amount deferred is recorded as income or expense at the time of the regulatory action.  A write-off of regulatory assets and costs not recovered may be required if all or a portion of the regulated operations have rates that are no longer:
	•	established by independent, third-party regulators;
	•	designed to recover the specific entity’s costs of providing regulated services; and
	•	set at levels that will recover our costs when considering the demand and competition for our services.
	In December 2013, the KCC approved a settlement agreement for the separation of our Kansas Gas Service natural gas distribution business to ONE Gas from ONEOK. The terms of the settlement agreement provided that amounts previously recorded as a regulatory asset related to ONEOK’s acquisition of Kansas Gas Service in 1997 would no longer be recovered in rates. As a result, the carrying amount of the regulatory asset was written off, and we recorded a noncash charge to income of approximately $10.2 million in the fourth quarter 2013.
	At December 31, 2013 and 2012, we recorded regulatory assets of approximately $383.6 million and $585.0 million, respectively, which are being recovered or are expected to be recovered as a result of various approved rate proceedings.  Of these amounts, the total regulatory assets related to our natural gas distribution business were $376.8 million and $577.1 million at December 31, 2013 and 2012, respectively. The natural gas distribution balances included approximately $341.1 million and $499.4 million related to our pension and postretirement benefit plans at December 31, 2013 and 2012, respectively, which are discussed in Note N.  Regulatory assets are being recovered as a result of approved rate proceedings over varying time periods up to 25 years.  These assets are reflected in other assets on our Consolidated Balance Sheets.
Pension and Postretirement Employee Benefits	'
	Pension and Postretirement Employee Benefits - We have defined benefit retirement plans covering certain full-time employees. We sponsor welfare plans that provide postretirement medical and life insurance benefits to certain employees who retire with at least five years of service.  Our actuarial consultant calculates the expense and liability related to these plans and uses statistical and other factors that attempt to anticipate future events.  These factors include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, age and employment periods.  In determining the projected benefit obligations and costs, assumptions can change from period to period and may result in material changes in the costs and liabilities we recognize.  See Note N for more discussion of pension and postretirement employee benefits.
	We determine our overall expected long-term rate of return on plan assets, based on our review of historical returns and economic growth models.
	We determine our discount rates annually.  We estimate our discount rate based upon a comparison of the expected cash flows associated with our future payments under our pension and postretirement obligations to a hypothetical bond portfolio created using high-quality bonds that closely match expected cash flows.  Bond portfolios are developed by selecting a bond for each of the next 60 years based on the maturity dates of the bonds.  Bonds selected to be included in the portfolios are only those rated by Moody’s as AA- or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.
Income Taxes	'
	Income Taxes - Deferred income taxes are recorded for the difference between the financial statement and income tax basis of assets and liabilities and carryforward items, based on income tax laws and rates existing at the time the temporary differences are expected to reverse.  The effect on deferred taxes of a change in tax rates is deferred and amortized for operations regulated by the OCC, KCC, RRC and various municipalities in Texas, if, as a result of an action by a regulator, it is probable that the effect of the change in tax rates will be recovered from or returned to customers through future rates.  For all other operations, the effect is recognized in income in the period that includes the enactment date.  We continue to amortize previously deferred investment tax credits for ratemaking purposes over the period prescribed by the OCC, KCC, RRC and various municipalities in Texas.
	We utilize a more-likely-than-not recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position that is taken or expected to be taken in a tax return.  We reflect penalties and interest as part of income tax expense as they become applicable for tax provisions that do not meet the more-likely-than-not recognition threshold and measurement attribute.  During 2013, 2012 and 2011, our tax positions did not require an establishment of a material reserve.
	We file numerous consolidated and separate income tax returns with federal tax authorities of the United States and Canada, along with the tax authorities of several states.  There are no United States federal audits or statute waivers at this time. See Note O for additional discussion of income taxes.
Asset Retirement Obligations	'
	Asset Retirement Obligations - Asset retirement obligations represent legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development and/or normal use of the asset.  Certain long-lived assets that comprise our natural gas distribution systems and ONEOK Partners’ natural gas gathering and processing, natural gas liquids and pipeline facilities are subject to agreements or regulations that give rise to an asset retirement obligation for removal or other disposition costs associated with retiring the assets in place upon the discontinued use of the assets. We recognize the fair value of a liability for an asset-retirement obligation in the period when it is incurred if a reasonable estimate of the fair value can be made.  We are not able to estimate reasonably the fair value of the asset retirement obligations for portions of our and ONEOK Partners’ assets because the settlement dates are indeterminable given the expected continued use of the assets with proper maintenance. We expect our former natural gas distribution assets and ONEOK Partners’ pipeline assets, for which we are unable to estimate reasonably the fair value of the asset retirement obligation, will continue to operate as long as natural gas supply and demand for natural gas and natural gas liquids exists. Based on the widespread use of natural gas for heating and cooking activities by residential users and electric-power generation by commercial users, as well as use of natural gas liquids by the petrochemical industry, we and ONEOK Partners expect supply and demand to exist for the foreseeable future.
	For our assets where we are able to make an estimate, the fair value of the liability is added to the carrying amount of the associated asset, and this additional carrying amount is depreciated over the life of the asset.  The liability is accreted at the end of each period through charges to operating expense.  If the obligation is settled for an amount other than the carrying amount of the liability, we will recognize a gain or loss on settlement.  The depreciation and accretion expense are immaterial to our consolidated financial statements.
	In accordance with long-standing regulatory treatment, we collect, through rates, the estimated costs of removal on certain regulated properties through depreciation expense, with a corresponding credit to accumulated depreciation and amortization. These removal costs collected through our rates include costs attributable to legal and nonlegal removal obligations; however, the amounts collected that are in excess of these nonlegal asset-removal costs incurred are accounted for as a regulatory liability for financial reporting purposes. Historically, with the exception of the regulatory authority in Kansas, the regulatory authorities that have jurisdiction over our regulated operations have not required us to quantify or disclose this amount; rather, these costs are addressed prospectively in depreciation rates and are set in each general rate order. We have made an estimate of our regulatory liability using current rates since the last general rate order in each of our jurisdictions; however, for financial reporting purposes, significant uncertainty exists regarding the future disposition of this regulatory liability, pending, among other issues, clarification of regulatory intent.  We continue to monitor the regulatory requirements, and the liability may be adjusted as more information is obtained.  We record the estimated asset removal obligation in noncurrent liabilities in other deferred credits on our Consolidated Balance Sheets.  To the extent this estimated liability is adjusted, such amounts will be reclassified between accumulated depreciation and amortization and other deferred credits and therefore will not have an impact on earnings.
Contingencies	'
	Contingencies - Our accounting for contingencies covers a variety of business activities, including contingencies for legal and environmental exposures.  We accrue these contingencies when our assessments indicate that it is probable that a liability has been incurred or an asset will not be recovered and an amount can be estimated reasonably.  We expense legal fees as incurred and base our legal liability estimates on currently available facts and our estimates of the ultimate outcome or resolution. Accruals for estimated losses from environmental remediation obligations generally are recognized no later than the completion of a remediation feasibility study.  Recoveries of environmental remediation costs from other parties are recorded as assets when their receipt is deemed probable.  Actual results may differ from our estimates resulting in an impact, positive or negative, on earnings.  See Note R for additional discussion of contingencies.
Share-Based Payments	'
	Share-Based Payments - We expense the fair value of share-based payments net of estimated forfeitures.  We estimate forfeiture rates based on historical forfeitures under our share-based payment plans.
Earnings per Common Share	'
	Earnings per Common Share - Basic EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period.  Diluted EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period plus potentially dilutive components.  The dilutive components are calculated based on the dilutive effect for each quarter.  For fiscal-year periods, the dilutive components for each quarter are averaged to arrive at the fiscal year-to-date dilutive component.
Recently Issued Accounting Standards Update	'
	Recently Issued Accounting Standards Update - In July 2013, the FASB issued ASU 2013-10, “Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes,” which allows an entity to designate the Fed Funds Effective Swap rate (also known as the Overnight Index Swap rate, or OIS rate, in the United States) as a benchmark interest rate for hedge accounting purposes in addition to the interest rates on direct Treasury obligations of the United States government and LIBOR. In addition, this guidance removes the restriction on using different benchmark interest rates for similar hedges. This guidance was effective prospectively for qualifying new or redesignated hedging relationships entered into on or after July 17, 2013. We adopted this guidance with our September 30, 2013, Quarterly Report, and it did not impact materially our financial position or results of operations. See Note E for additional disclosures.
	In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income,” which requires presentation in a single location, either in a single note or parenthetically on the face of the financial statements, the effect of significant amounts reclassified from each component of accumulated other comprehensive income based on its source.  We adopted this guidance with our March 31, 2013, Quarterly Report, and it did not impact our financial position or results of operations. See Note K for additional disclosures.
	In July 2012, the FASB issued ASU 2012-02, “Testing Indefinite-lived Intangible Assets for Impairment,” which allows companies to perform a “qualitative” assessment to determine whether further impairment testing of indefinite-lived intangible assets is necessary.  Under the revised standard, an entity is not required to calculate the fair value of an indefinite-lived intangible asset and perform the quantitative impairment test unless the entity determines that it is more likely than not that the asset is impaired.  An entity has the option to bypass the qualitative assessment and perform the quantitative impairment test for any indefinite-lived intangible assets in any period.  We adopted this guidance for our annual assessments beginning in July 2013, and it did not impact our financial position or results of operations.
	In December 2011, the FASB issued ASU No. 2011-11, “Disclosures about Offsetting Assets and Liabilities,” which increases disclosures about offsetting assets and liabilities. In January 2013, the FASB issued ASU 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities,” which clarifies that the scope of ASU 2011-11 applies to derivatives accounted for in accordance with Topic 815, Derivatives and Hedging. New disclosures are required to enable users of financial statements to understand significant quantitative differences in balance sheets prepared under GAAP and International Financial Reporting Standards related to the offsetting of financial instruments, including derivatives. The existing GAAP guidance allowing balance sheet offsetting remains unchanged. This guidance was effective for interim and annual periods beginning on January 1, 2013, and was applied retrospectively for all comparative periods presented. The adoption of this guidance beginning with our March 31, 2013, Quarterly Report did not affect our financial condition, results of operations or cash flows.
Accounting Standards Update 2013-10 [Member]	'
Entity [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	' In July 2013, the FASB issued ASU 2013-10, bInclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes,b which allows an entity to designate the Fed Funds Effective Swap rate (also known as the Overnight Index Swap rate, or OIS rate, in the United States) as a benchmark interest rate for hedge accounting purposes in addition to the interest rates on direct Treasury obligations of the United States government and LIBOR. In addition, this guidance removes the restriction on using different benchmark interest rates for similar hedges. This guidance was effective prospectively for qualifying new or redesignated hedging relationships entered into on or after July 17, 2013.
Accounting Standards Update 2013-02 [Member]	'
Entity [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	'In February 2013, the FASB issued ASU 2013-02, bReporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income,b which requires presentation in a single location, either in a single note or parenthetically on the face of the financial statements, the effect of significant amounts reclassified from each component of accumulated other comprehensive income based on its source.B
Accounting Standards Update 2012-02 [Member]	'
Entity [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	'In July 2012, the FASB issued ASU 2012-02, bTesting Indefinite-lived Intangible Assets for Impairment,b which allows companies to perform a bqualitativeb assessment to determine whether further impairment testing of indefinite-lived intangible assets is necessary.B Under the revised standard, an entity is not required to calculate the fair value of an indefinite-lived intangible asset and perform the quantitative impairment test unless the entity determines that it is more likely than not that the asset is impaired.B An entity has the option to bypass the qualitative assessment and perform the quantitative impairment test for any indefinite-lived intangible assets in any period.B
Accounting Standards Update 2011-11 [Member]	'
Entity [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	'In December 2011, the FASB issued ASU No. 2011-11, bDisclosures about Offsetting Assets and Liabilities,b which increases disclosures about offsetting assets and liabilities. In January 2013, the FASB issued ASU 2013-01, bClarifying the Scope of Disclosures about Offsetting Assets and Liabilities,b which clarifies that the scope of ASU 2011-11 applies to derivatives accounted for in accordance with Topic 815, Derivatives and Hedging. New disclosures are required to enable users of financial statements to understand significant quantitative differences in balance sheets prepared under GAAP and International Financial Reporting Standards related to the offsetting of financial instruments, including derivatives. The existing GAAP guidance allowing balance sheet offsetting remains unchanged. This guidance was effective for interim and annual periods beginning on January 1, 2013, and was applied retrospectively for all comparative periods presented.

LONGTERM_DEBT_Accounting_Polic

LONG-TERM DEBT Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Debt, Policy [Policy Text Block]	'
	We amortize premiums, discounts and expenses incurred in connection with the issuance of long-term debt consistent with the terms of the respective debt instrument.

EMPLOYEE_BENEFIT_PLANS_Rate_of

EMPLOYEE BENEFIT PLANS Rate of return and discount rates accounting policy (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Pension and Other Postretirement Plans, Policy [Policy Text Block]	'
	Pension and Postretirement Employee Benefits - We have defined benefit retirement plans covering certain full-time employees. We sponsor welfare plans that provide postretirement medical and life insurance benefits to certain employees who retire with at least five years of service.  Our actuarial consultant calculates the expense and liability related to these plans and uses statistical and other factors that attempt to anticipate future events.  These factors include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, age and employment periods.  In determining the projected benefit obligations and costs, assumptions can change from period to period and may result in material changes in the costs and liabilities we recognize.  See Note N for more discussion of pension and postretirement employee benefits.
	We determine our overall expected long-term rate of return on plan assets, based on our review of historical returns and economic growth models.
	We determine our discount rates annually.  We estimate our discount rate based upon a comparison of the expected cash flows associated with our future payments under our pension and postretirement obligations to a hypothetical bond portfolio created using high-quality bonds that closely match expected cash flows.  Bond portfolios are developed by selecting a bond for each of the next 60 years based on the maturity dates of the bonds.  Bonds selected to be included in the portfolios are only those rated by Moody’s as AA- or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.

ONEOK_PARTNERS_Accounting_Poli

ONEOK PARTNERS Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Business Combinations Policy [Policy Text Block]	'
	ONEOK Partners accounted for this acquisition as a business combination, which, among other things, requires assets acquired and liabilities assumed to be measured at their acquisition-date fair values. The excess of the purchase price over the fair values of the identifiable assets acquired was recorded as goodwill.
Incentive Distribution Policy, Managing Member or General Partner, Description [Policy Text Block]	'
	We receive distributions from ONEOK Partners on our common and Class B units and our 2 percent general partner interest, which includes our incentive distribution rights.  Under ONEOK Partners’ partnership agreement, as amended, distributions are made to the partners with respect to each calendar quarter in an amount equal to 100 percent of available cash as defined in the ONEOK Partners partnership agreement (Partnership Agreement), as amended.  Available cash generally will be distributed 98 percent to limited partners and 2 percent to the general partner.  The general partner’s percentage interest in quarterly distributions is increased after certain specified target levels are met during the quarter.  In July 2011, the Partnership Agreement was amended to adjust the formula for distributing available cash among the general partner and limited partners to reflect the two-for-one unit split of ONEOK Partners’ common units.  Under the incentive distribution provisions, as set forth in ONEOK Partners’ partnership agreement, as amended, the general partner receives:
	•	15 percent of amounts distributed in excess of $0.3025 per unit;
	•	25 percent of amounts distributed in excess of $0.3575 per unit; and
	•	50 percent of amounts distributed in excess of $0.4675 per unit.
Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block]	'
	We account for the difference between the carrying amount of our investment in ONEOK Partners and the underlying book value arising from issuance of common units by ONEOK Partners as an equity transaction.  If ONEOK Partners issues common units at a price different than our carrying value per unit, we account for the premium or deficiency as an adjustment to paid-in capital.  As a result of ONEOK Partners’ issuance of common units, we recognized an increase to paid-in capital of approximately $87.3 million, net of taxes, in 2013 and a decrease to paid-in capital of approximately $51.1 million, net of taxes, in 2012.

SEGMENTS_Accounting_Policies_P

SEGMENTS Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Segment Accounting Policy [Text Block]	'
	We evaluate performance based principally on each segment’s operating income and equity earnings. The accounting policies of the segments are the same as those described in Note A.  Intersegment sales are recorded on the same basis as sales to unaffiliated customers and are discussed in further detail in Note Q.  Net margin is comprised of total revenues less cost of sales and fuel.  Cost of sales and fuel includes commodity purchases, fuel, and storage and transportation costs.

EXIT_ACTIVITIES_Tables

EXIT ACTIVITIES (Tables)	12 Months Ended
	Dec. 31, 2013
EXIT ACTIVITIES [Abstract]	'
Schedule of Restructuring and Related Costs [Table Text Block]	'
	The following table summarizes the change in our liability related to released capacity contracts for the period indicated:
		Year Ended
		31-Dec-13
		(Millions of dollars)
	Beginning balance	$	—
	Noncash charges	138.6
	Settlements	(17.7		)
	Accretion	1.1
	Ending balance	$	122

DISCONTINUED_OPERATIONS_Tables

DISCONTINUED OPERATIONS (Tables)	12 Months Ended
	Dec. 31, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued Operations	'
	The amounts of revenue, costs and income taxes reported in discontinued operations are set forth in the table below for the periods indicated:
		One Month Ended			Year Ended
		January 31,			December 31,
		2012			2011
		(Thousands of dollars)
	Revenues	$	27,607		$	313,371
	Cost of sales and fuel	25,961			302,561
	Net margin	1,646			10,810
	Operating costs	408			7,147
	Depreciation and amortization	8			128
	Operating income	1,230			3,535
	Other income (expense), net	—			(50		)
	Income taxes	(468		)	(1,255		)
	Income from discontinued operations, net	$	762		$	2,230

FAIR_VALUE_MEASUREMENTS_Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Recurring Fair Value Measurments	'
	Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements for the periods indicated:
		December 31, 2013
		Level 1			Level 2			Level 3			Total - Gross			Netting			Total - Net
		(Thousands of dollars)
	Assets
	Derivatives (a)
	Commodity contracts
	Financial contracts	$	4,477		$	647		$	3,094		$	8,218		$	(2,850	)	$	5,368
	Physical contracts	—			4			1,764			1,768			(1,157		)	611
	Interest-rate contracts	—			54,503			—			54,503			—			54,503
	Total derivative assets	4,477			55,154			4,858			64,489			(4,007		)	60,482
	Fair value of firm commitments (b)	—			—			599			599			—			599
	Available-for-sale investment securities (b)	1,569			—			—			1,569			—			1,569
	Total assets	$	6,046		$	55,154		$	5,457		$	66,657		$	(4,007	)	$	62,650
	Liabilities
	Derivatives (a)
	Commodity contracts
	Financial contracts	$	(7,624	)	$	(776	)	$	(3,435	)	$	(11,835	)	$	10,767		$	(1,068	)
	Physical contracts	—			(4		)	(4,117		)	(4,121		)	1,157			(2,964		)
	Total derivative liabilities	$	(7,624	)	$	(780	)	$	(7,552	)	$	(15,956	)	$	11,924		$	(4,032	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets as energy marketing and risk management assets and liabilities, other assets and other deferred credits on a net basis. We net derivative assets and liabilities, including cash collateral, when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2013, we held no cash collateral and had posted $15.7 million of cash collateral with various counterparties.
	(b) - Included in our Consolidated Balance Sheets as other assets.
		December 31, 2012
		Level 1			Level 2			Level 3			Total - Gross			Netting			Total - Net
		(Thousands of dollars)
	Assets
	Derivatives (a)
	Commodity contracts
	Financial contracts	$	69,957		$	10,780		$	7,107		$	87,844		$	(51,602	)	$	36,242
	Physical contracts	—			2,083			2,032			4,115			(151		)	3,964
	Interest-rate contracts	—			10,923			—			10,923			—			10,923
	Total derivative assets	69,957			23,786			9,139			102,882			(51,753		)	51,129
	Trading securities (b)	5,978			—			—			5,978			—			5,978
	Available-for-sale investment securities (c)	2,027			—			—			2,027			—			2,027
	Total assets	$	77,962		$	23,786		$	9,139		$	110,887		$	(51,753	)	$	59,134
	Liabilities
	Derivatives (a)
	Commodity contracts
	Financial contracts	$	(35,172	)	$	(1,737	)	$	(7,177	)	$	(44,086	)	$	33,878		$	(10,208	)
	Physical contracts	—			—			(279		)	(279		)	151			(128		)
	Total derivative liabilities	(35,172		)	(1,737		)	(7,456		)	(44,365		)	34,029			(10,336		)
	Fair value of firm commitments (d)	—			—			(1,280		)	(1,280		)	—			(1,280		)
	Total liabilities	$	(35,172	)	$	(1,737	)	$	(8,736	)	$	(45,645	)	$	34,029		$	(11,616	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets as energy marketing and risk management assets and liabilities, other assets and other deferred credits on a net basis. We net derivative assets and liabilities, including cash collateral, when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2012, we held $17.7 million of cash collateral and had posted $4.5 million of cash collateral with various counterparties.
	(b) - Included in our Consolidated Balance Sheets as other current assets.
	(c) - Included in our Consolidated Balance Sheets as other assets.
	(d) - Included in our Consolidated Balance Sheets as other current liabilities and other deferred credits.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	'
	The following tables set forth the reconciliation of our Level 3 fair value measurements for the periods indicated:
		Derivative			Fair Value of			Total
		Assets			Firm
		(Liabilities)			Commitments
		(Thousands of dollars)
	1-Jan-13	$	1,683		$	(1,280	)	$	403
	Total realized/unrealized gains (losses):
	Included in earnings (a)	(5,627		)	1,879			(3,748		)
	Included in other comprehensive income (loss)	800			—			800
	Settlements	450			—			450
	31-Dec-13	$	(2,694	)	$	599		$	(2,095	)
	Total gains (losses) for the period included in earnings attributable to the change in	$	(804	)	$	670		$	(134	)
	unrealized gains (losses) relating to assets and liabilities still held as of
	December 31, 2013 (a)
	(a) - Reported in revenues and cost of sales and fuel in our Consolidated Statements of Income.
		Derivative			Fair Value of			Total
		Assets			Firm
		(Liabilities)			Commitments
		(Thousands of dollars)
	1-Jan-12	$	25,104		$	(7,283	)	$	17,821
	Total realized/unrealized gains (losses):
	Included in earnings (a)	(13,503		)	6,003			(7,500		)
	Included in other comprehensive income (loss)	(5,587		)	—			(5,587		)
	Sale of discontinued operations	(3,636		)	—			(3,636		)
	Transfers out of Level 3	(695		)	—			(695		)
	31-Dec-12	$	1,683		$	(1,280	)	$	403
	Total gains (losses) for the period included in earnings attributable to the change in	$	1,971		$	(112	)	$	1,859
	unrealized gains (losses) relating to assets and liabilities still held as of
	December 31, 2012 (a)
	(a) - Reported in revenues and cost of sales and fuel in our Consolidated Statements of Income.

RISK_MANAGEMENT_AND_HEDGING_AC1

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES (Tables)	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Fair value of derivatives	'
	Fair Values of Derivative Instruments - The following table sets forth the fair values of our derivative instruments for our continuing and discontinued operations for the periods indicated:
		December 31, 2013									December 31, 2012
		Fair Values of Derivatives (a)									Fair Values of Derivatives (a)
		Assets					(Liabilities)				Assets					(Liabilities)
		(Thousands of dollars)
	Derivatives designated as hedging instruments
	Commodity contracts
	Financial contracts	$	8,011		(b)		$	(10,573	)		$	47,516		(c)		$	(4,885	)
	Physical contracts	1,064					(3,463		)		56					(126		)
	Interest-rate contracts	54,503					—				10,923					—
	Total derivatives designated as hedging instruments	63,578					(14,036		)		58,495					(5,011		)
	Derivatives not designated as hedging instruments
	Commodity contracts
	Nontrading instruments
	Financial contracts	202					(1,262		)		24,970					(25,009		)
	Physical contracts	704					(658		)		4,059					(153		)
	Trading instruments
	Financial contracts	5					—				15,358					(14,192		)
	Total derivatives not designated as hedging instruments	911					(1,920		)		44,387					(39,354		)
	Total derivatives	$	64,489				$	(15,956	)		$	102,882				$	(44,365	)
	(a) - Included on a net basis in energy marketing and risk-management assets and liabilities or other assets on our Consolidated Balance Sheets.
	(b) - Includes $5.8 million of derivative assets associated with cash flow hedges of inventory that were adjusted to reflect the lower of cost or market value. The deferred gains associated with these assets have been reclassified from accumulated other comprehensive income (loss).
	(c) - Includes $16.9 million
Notional amounts of derivative instruments	'
	Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for derivative instruments held for our continuing and discontinued operations for the periods indicated:
				December 31, 2013							December 31, 2012
		Contract		Purchased/				Sold/			Purchased/				Sold/
		Type		Payor				Receiver			Payor				Receiver
	Derivatives designated as hedging instruments:
	Cash flow hedges
	Fixed price
	-Natural gas (Bcf)	Futures, forwards and swaps		—				(65.0	)		—				(85.1	)
	-Crude oil and NGLs (MMBbl)	Futures, forwards and swaps		—				(4.0	)		—				(1.1	)
	Basis
	-Natural gas (Bcf)	Futures, forwards and swaps		—				(57.4	)		—				(56.3	)
	Interest-rate contracts (Millions of dollars)	Forward-starting		$	400			—			$	400			—
		swaps
	Fair value hedges
	Basis
	-Natural gas (Bcf)	Futures, forwards and swaps		1.1				(1.1	)		59.1				(59.1	)
	Derivatives not designated as hedging instruments:
	Fixed price
	-Natural gas (Bcf)	Futures, forwards and swaps		5.8				(9.7	)		60.7				(60.4	)
		Options		—				—			102.1				(100.8	)
	-Crude oil and NGLs (MMBbl)	Futures, forwards and swaps		0.3				(0.3	)		—				—
	Basis
	-Natural gas (Bcf)	Futures, forwards and swaps		8.5				(11.2	)		80.2				(81.7	)
	Index
	-Natural gas (Bcf)	Futures, forwards and swaps		1.8				—			20.3				(22.3	)
Schedule of cash flow hedging instruments effect on comprehensive income (loss)	'
	The following table sets forth the effect of cash flow hedges recognized in other comprehensive income (loss) for the periods indicated:
	Derivatives in Cash Flow		Years Ended December 31,
	Hedging Relationships		2013				2012				2011
			(Thousands of dollars)
	Commodity contracts		$	(15,433	)		$	62,898			$	117,508
	Interest-rate contracts		46,616				(29,471		)		(128,666		)
	Total gain (loss) recognized in other comprehensive income (loss) on derivatives		$	31,183			$	33,427			$	(11,158	)
	(effective portion)
Schedule of cash flow hedging instruments effect on income	'
	The following tables set forth the effect of cash flow hedges on our Consolidated Statements of Income for the periods indicated:
			Location of Gain (Loss) Reclassified from
	Derivatives in Cash Flow		Accumulated Other Comprehensive Income		Years Ended December 31,
	Hedging Relationships		(Loss) into Net Income (Effective Portion)		2013				2012				2011
					(Thousands of dollars)
	Commodity contracts		Revenues		$	19,049			$	140,862			$	48,601
	Commodity contracts		Cost of sales and fuel		(14,320		)		(73,881		)		89,618
	Interest-rate contracts		Interest expense		(14,560		)		(7,155		)		(480		)
	Total gain (loss) reclassified from accumulated other comprehensive income				$	(9,831	)		$	59,826			$	137,739
	(loss) into net income on derivatives (effective portion)
Schedule of derivatives not designated as hedging effect on income	'
	Other Derivative Instruments - The following table sets forth the effect of our derivative instruments that are not part of a hedging relationship on our Consolidated Statements of Income for our continuing and discontinued operations for the periods indicated:
	Derivatives Not Designated as		Location of Gain (Loss)		Years Ended December 31,
	Hedging Instruments				2013				2012				2011
					(Thousands of dollars)
	Commodity contracts - trading		Revenues		$	(2,051	)		$	2,413			$	1,796
	Commodity contracts - non-trading (a)		Cost of sales and fuel		(2,266		)	(b)	5,956				16,178
	Total gain (loss) recognized in income on derivatives				$	(4,317	)		$	8,369			$	17,974
	(a) - Amounts are presented net of deferred losses associated with derivatives entered into by our Natural Gas Distribution segment.
	(b) - Includes losses of $2.2 million for the year ended December 31, 2013, on certain derivatives derecognized that were designated previously as fair value hedges of firm transportation commitments that no longer meet the definition of a firm commitment.

PROPERTY_PLANT_AND_EQUIPMENT_T

PROPERTY, PLANT AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Abstract]	'
Components of Property, Plant and Equipment	'
	The following table sets forth our property, plant and equipment by property type, for the periods indicated:
		Estimated Useful	December 31,			December 31,
		Lives (Years)	2013			2012
			(Thousands of dollars)
	Non-Regulated
	Gathering pipelines and related equipment	5 to 40	$	2,173,271		$	1,638,037
	Processing and fractionation and related equipment	5 to 40	2,295,983			1,625,146
	Storage and related equipment	5 to 54	362,704			335,237
	Transmission pipelines and related equipment	22 to 54	302,718			311,038
	General plant and other	2 to 60	402,523			348,636
	Construction work in process	—	1,112,182			881,788
	Regulated
	Natural gas distribution pipelines and related equipment	15 to 80	3,703,593			3,512,660
	Storage and related equipment	5 to 54	135,922			136,938
	Natural gas transmission pipelines and related equipment	5 to 77	1,850,559			1,796,683
	Natural gas liquids transmission pipelines and related equipment	5 to 80	2,049,461			1,490,511
	General plant and other	2 to 85	324,703			309,119
	Construction work in process	—	822,537			703,198
	Property, plant and equipment		15,536,156			13,088,991
	Accumulated depreciation and amortization - non-regulated		(1,112,192		)	(954,398		)
	Accumulated depreciation and amortization - regulated		(2,126,460		)	(2,020,253		)
	Net property, plant and equipment		$	12,297,504		$	10,114,340
Average Depreciation Rates for Regulated Property	'
	The average depreciation rates for our regulated property are set forth, by segment, in the following table for the periods indicated:
		Years Ended December 31,
	Regulated Property	2013	2012		2011
	ONEOK Partners	2.0% - 2.2%	1.9% - 2.2%		1.9% - 2.2%
	Natural Gas Distribution	2.0% - 3.0%	2.0% - 3.0%		2.0% - 2.9%

GOODWILL_AND_INTANGIBLE_ASSETS1

GOODWILL AND INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill by Segment	'
	Goodwill - The following table sets forth our goodwill by segment for the periods indicated:
		ONEOK				Natural Gas				Energy		Total
		Partners				Distribution				Services
		(Thousands of dollars)
	31-Dec-12	$	433,535			$	157,953			$	—	$	591,488
	Acquisitions	92,000				—				—		92,000
	31-Dec-13	$	525,535			$	157,953			$	—	$	683,488
Gross Carrying Amount and Accumulated Amortization of Intangible Assets	'
	Intangible Assets - The following table sets forth the gross carrying amount and accumulated amortization of intangible assets for the periods indicated:
			December 31,				December 31,
			2013				2012
			(Thousands of dollars)
	Gross intangible assets		$	565,215			$	462,214
	Accumulated amortization		(66,188		)		(57,496		)
	Net intangible assets		$	499,027			$	404,718

LONGTERM_DEBT_Tables

LONG-TERM DEBT (Tables)	12 Months Ended
	Dec. 31, 2013
Long-term Debt, Unclassified [Abstract]	'
Long-Term Debt	'
		December 31,			December 31,
		2013			2012
		(Thousands of dollars)
	ONEOK
	$400,000 at 5.2% due 2015	$	400,000		$	400,000
	$700,000 at 4.25% due 2022	700,000			700,000
	$100,000 at 6.5% due 2028	87,649			87,662
	$100,000 at 6.875% due 2028	100,000			100,000
	$400,000 at 6.0% due 2035	400,000			400,000
	Other	1,323			1,528
	Total ONEOK senior notes payable	1,688,972			1,689,190
	ONEOK Partners
	$650,000 at 3.25% due 2016	650,000			650,000
	$450,000 at 6.15% due 2016	450,000			450,000
	$400,000 at 2.0% due 2017	400,000			400,000
	$425,000 at 3.2% due 2018	425,000			—
	$500,000 at 8.625% due 2019	500,000			500,000
	$900,000 at 3.375 % due 2022	900,000			900,000
	$425,000 at 5.0 % due 2023	425,000			—
	$600,000 at 6.65% due 2036	600,000			600,000
	$600,000 at 6.85% due 2037	600,000			600,000
	$650,000 at 6.125% due 2041	650,000			650,000
	$400,000 at 6.2% due 2043	400,000			—
	Guardian Pipeline
	Average 7.85%, due 2022	67,208			74,857
	Total ONEOK Partners senior notes payable	6,067,208			4,824,857
	Total long-term notes payable	7,756,180			6,514,047
	Unamortized portion of terminated swaps	25,340			27,058
	Unamortized debt discount	(15,889		)	(14,878		)
	Current maturities	(10,656		)	(10,855		)
	Long-term debt	$	7,754,975		$	6,515,372
Aggregate maturities of long-term debt outstanding	'
		ONEOK			ONEOK			Guardian		Total
					Partners			Pipeline
		(Millions of dollars)
	2014	$	3		$	—		$	7.7	$	10.7
	2015	$	403		$	—		$	7.7	$	410.7
	2016	$	3		$	1,100.00		$	7.7	$	1,110.70
	2017	$	3		$	400		$	7.7	$	410.7
	2018	$	3		$	425		$	7.7	$	435.7

EQUITY_Tables

EQUITY (Tables)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Quarterly dividends per share paid on common stock	'
	Dividends - Dividends paid totaled $304.7 million, $262.0 million and $227.0 million for 2013, 2012 and 2011, respectively. The following table sets forth the quarterly dividends per share declared and paid on our common stock for the periods indicated:
		Years Ended December 31,
		2013		2012		2011
	First Quarter	$	0.36	$	0.305	$	0.26
	Second Quarter	$	0.36	$	0.305	$	0.26
	Third Quarter	$	0.38	$	0.33	$	0.28
	Fourth Quarter	$	0.38	$	0.33	$	0.28
	Total	$	1.48	$	1.27	$	1.08

ACCUMULATED_OTHER_COMPREHENSIV1

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	12 Months Ended
	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'
Accumulated other comprehensive income (loss)	'
	The following table sets forth the balance in accumulated other comprehensive income (loss) for the periods indicated:
		Unrealized Gains			Unrealized			Pension and			Accumulated
		(Losses) on Energy			Holding Gains			Postretirement			Other
		Marketing and			(Losses)			Benefit Plan			Comprehensive
		Risk-Management			on Investment			Obligations (a)			Income (Loss) (a)
		Assets/Liabilities (a)			Securities (a)
		(Thousands of dollars)
	1-Jan-12	$	(55,367	)	$	987		$	(151,741	)	$	(206,121	)
	Other comprehensive income (loss) before	16,709			47			(47,004		)	(30,248		)
	reclassifications
	Amounts reclassified from accumulated other	(16,372		)	—			35,943			19,571
	comprehensive income (loss)
	Other comprehensive income	337			47			(11,061		)	(10,677		)
	(loss) attributable to ONEOK
	31-Dec-12	(55,030		)	1,034			(162,802		)	(216,798		)
	Other comprehensive income (loss) before	8,842			(177		)	37,144			45,809
	reclassifications
	Amounts reclassified from accumulated other	3,020			—			45,982			49,002
	comprehensive income (loss)
	Other comprehensive income	11,862			(177		)	83,126			94,811
	(loss) attributable to ONEOK
	31-Dec-13	$	(43,168	)	$	857		$	(79,676	)	$	(121,987	)

EARNINGS_PER_SHARE_Tables

EARNINGS PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	The following tables set forth the computation of basic and diluted EPS from continuing operations for the periods indicated:
		Year Ended December 31, 2013
		Income		Shares	Per Share
					Amount
		(Thousands, except per share amounts)
	Basic EPS from continuing operations
	Income from continuing operations attributable to ONEOK available for	$	266,533	206,044	$	1.29
	common stock
	Diluted EPS from continuing operations
	Effect of options and other dilutive securities	—		3,651
	Income from continuing operations attributable to ONEOK available for	$	266,533	209,695	$	1.27
	common stock and common stock equivalents
		Year Ended December 31, 2012
		Income		Shares	Per Share
					Amount
		(Thousands, except per share amounts)
	Basic EPS from continuing operations
	Income from continuing operations attributable to ONEOK available for	$	346,340	206,140	$	1.68
	common stock
	Diluted EPS from continuing operations
	Effect of options and other dilutive securities	—		4,570
	Income from continuing operations attributable to ONEOK available for	$	346,340	210,710	$	1.64
	common stock and common stock equivalents
		Year Ended December 31, 2011
		Income		Shares	Per Share
					Amount
		(Thousands, except per share amounts)
	Basic EPS from continuing operations
	Income from continuing operations attributable to ONEOK available for	$	358,364	209,344	$	1.71
	common stock
	Diluted EPS from continuing operations
	Effect of options and other dilutive securities	—		5,154
	Income from continuing operations attributable to ONEOK available for	$	358,364	214,498	$	1.67
	common stock and common stock equivalents

SHAREBASED_PAYMENTS_Tables

SHARE-BASED PAYMENTS (Tables)	12 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Schedule of Restricted Stock Unit and Performance Unit Activity	'
	The following tables set forth activity and various statistics for our restricted stock unit awards:
		Number of			Weighted
		Shares			Average Price
	Nonvested December 31, 2012	1,020,600			$	27.21
	Granted	167,301			$	47.46
	Released to participants	(384,883	)		$	19.06
	Forfeited	(26,422	)		$	37.23
	Nonvested December 31, 2013	776,596			$	35.27
		2013				2012		2011
	Weighted-average grant date fair value (per share)	$	47.46			$	36.65	$	28.5
	Fair value of shares granted (thousands of dollars)	$	7,940			$	11,030	$	11,728
	Performance-Unit Activity
	As of December 31, 2013, we had $22.5 million of total unrecognized compensation cost related to the nonvested performance-unit awards, which is expected to be recognized over a weighted-average period of 1.7 years.  The following tables set forth activity and various statistics related to the performance-unit awards and the assumptions used in the valuations of the 2013, 2012 and 2011 grants at the grant date:
		Number of			Weighted
		Units			Average Price
	Nonvested December 31, 2012	2,133,157			$	32.74
	Granted	377,200			$	52.34
	Released to participants	(801,354	)		$	24.05
	Forfeited	(56,858	)		$	42.53
	Nonvested December 31, 2013	1,652,145			$	41.1
		2013		2012		2011
	Volatility (a)	22.27%		27.00%		39.91%
	Dividend Yield	3.04%		2.86%		3.30%
	Risk-free Interest Rate	0.42%		0.38%		1.33%
	(a) - Volatility was based on historical volatility over three years using daily stock price observations.
		2013				2012		2011
	Weighted-average grant date fair value (per share)	$	52.34			$	42.39	$	34.68
	Fair value of shares granted (thousands of dollars)	$	19,742			$	25,466	$	29,186

EMPLOYEE_BENEFIT_PLANS_Tables

EMPLOYEE BENEFIT PLANS (Tables)	12 Months Ended
	Dec. 31, 2013
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]	'
Pension and postretirement benefit plans obligations and fair value of plan assets	'
	Obligations and Funded Status - The following tables set forth our pension and postretirement benefit plans benefit obligations and fair value of plan assets for the periods indicated:
		Pension Benefits						Postretirement Benefits
		December 31,						December 31,
		2013			2012			2013			2012
	Change in Benefit Obligation	(Thousands of dollars)
	Benefit obligation, beginning of period	$	1,313,560		$	1,215,932		$	299,172		$	286,044
	Service cost	22,968			21,301			4,612			4,960
	Interest cost	54,449			59,237			11,713			13,893
	Plan participants’ contributions	—			—			4,293			5,851
	Actuarial loss (gain)	(110,552		)	105,732			(29,460		)	9,935
	Benefits paid	(58,976		)	(88,642		)	(18,411		)	(21,380		)
	Plan amendment	—			—			17,228			(131		)
	Benefit obligation, end of period	1,221,449			1,313,560			289,147			299,172
	Change in Plan Assets
	Fair value of plan assets, beginning of period	995,264			902,235			148,162			124,163
	Actual return on plan assets	176,889			90,026			27,483			14,273
	Employer contributions	—			91,881			866			10,728
	Benefits paid	(59,404		)	(88,878		)	(876		)	(1,002		)
	Fair value of assets, end of period	1,112,749			995,264			175,635			148,162
	Balance at December 31	$	(108,700	)	$	(318,296	)	$	(113,512	)	$	(151,010	)
	Current liabilities	$	(5,457	)	$	(4,695	)	$	—		$	—
	Noncurrent liabilities	(103,243		)	(313,601		)	(113,512		)	(151,010		)
	Balance at December 31	$	(108,700	)	$	(318,296	)	$	(113,512	)	$	(151,010	)
Components of net periodic benefit cost for pension and postretirement benefit plans	'
	Components of Net Periodic Benefit Cost - The following tables set forth the components of net periodic benefit cost for our pension and postretirement benefit plans for the periods indicated:
		Pension Benefits
		Years Ended December 31,
		2013			2012			2011
		(Thousands of dollars)
	Components of net periodic benefit cost
	Service cost	$	22,968		$	21,301		$	20,013
	Interest cost	54,449			59,237			58,757
	Expected return on assets	(81,272		)	(82,756		)	(75,500		)
	Amortization of unrecognized prior service cost	920			969			1,018
	Amortization of net loss	66,282			48,439			35,708
	Settlements	1,338			1,401			—
	Net periodic benefit cost	$	64,685		$	48,591		$	39,996
		Postretirement Benefits
		Years Ended December 31,
		2013			2012			2011
		(Thousands of dollars)
	Components of net periodic benefit cost
	Service cost	$	4,612		$	4,960		$	4,987
	Interest cost	11,713			13,893			15,632
	Expected return on assets	(12,259		)	(10,687		)	(10,272		)
	Amortization of unrecognized net asset at adoption	284			2,874			3,189
	Amortization of unrecognized prior service cost	(6,442		)	(8,252		)	(2,518		)
	Amortization of net loss	12,605			13,184			8,123
	Net periodic benefit cost	$	10,513		$	15,972		$	19,141
Amounts recognized in other comprehensive income (loss)	'
	Other Comprehensive Income (Loss) - The following tables set forth the amounts recognized in other comprehensive income (loss) related to our pension benefits and postretirement benefits for the periods indicated:
		Pension Benefits
		Years Ended December 31,
		2013			2012			2011
		(Thousands of dollars)
	Regulatory asset gain (loss)	$	(110,437	)	$	67,472		$	114,625
	Net gain (loss) arising during the period	201,251			(103,199		)	(182,987		)
	Amortization of regulatory asset	(44,378		)	(32,527		)	(23,265		)
	Amortization of prior service credit	920			969			1,018
	Amortization of loss	67,620			49,839			35,708
	Deferred income taxes	(44,473		)	6,748			21,236
	Total recognized in other comprehensive income (loss)	$	70,503		$	(10,698	)	$	(33,665	)
		Postretirement Benefits
		Years Ended December 31,
		2013			2012			2011
		(Thousands of dollars)
	Regulatory asset gain (loss)	$	(7,674	)	$	4,376		$	7,389
	Net gain (loss) arising during the period	44,685			(6,348		)	(40,765		)
	Amortization of regulatory asset	(5,643		)	(6,557		)	(7,214		)
	Amortization of transition obligation	284			2,874			3,189
	Amortization of prior service cost	(6,442		)	(8,252		)	(2,518		)
	Amortization of loss	12,605			13,184			8,123
	Plan amendment	(17,228		)	131			44,562
	Deferred income taxes	(7,964		)	229			(4,938		)
	Total recognized in other comprehensive income (loss)	$	12,623		$	(363	)	$	7,828
Amounts in accumulated other comprehensive income (loss)	'
	The table below sets forth the amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense for the periods indicated:
		Pension Benefits						Postretirement Benefits
		December 31,						December 31,
		2013			2012			2013			2012
		(Thousands of dollars)
	Transition obligation	$	—		$	—		$	—		$	(283	)
	Prior service credit (cost)	(1,102		)	(2,022		)	14,631			38,301
	Accumulated loss	(415,375		)	(684,245		)	(59,362		)	(116,652		)
	Accumulated other comprehensive loss	(416,477		)	(686,267		)	(44,731		)	(78,634		)
	before regulatory assets
	Regulatory asset for regulated entities	288,017			442,833			43,254			56,571
	Accumulated other comprehensive loss	(128,460		)	(243,434		)	(1,477		)	(22,063		)
	after regulatory assets
	Deferred income taxes	49,689			94,161			572			8,534
	Accumulated other comprehensive loss,	$	(78,771	)	$	(149,273	)	$	(905	)	$	(13,529	)
	net of tax
Amounts in either accumulated comprehensive income (loss) or regulatory assets expected to be recognized as components of net periodic benefit expense	'
	The following table sets forth the amounts recognized in either accumulated comprehensive income (loss) or regulatory assets expected to be recognized as components of net periodic benefit expense in the next fiscal year. The table does not include amounts applicable to employees of ONE Gas, as those amounts are expected to be recognized by ONE Gas as a result of the separation of the natural gas distribution business.
		Pension			Postretirement
		Benefits			Benefits
	Amounts to be recognized in 2014	(Thousands of dollars)
	Transition obligation	$	—		$	—
	Prior service credit (cost)	$	193		$	(1,662	)
	Net loss	$	15,021		$	833
Weighted-average assumptions used to determine benefit obligations and net periodic benefit costs	'
	Actuarial Assumptions - The following table sets forth the weighted-average assumptions used to determine benefit obligations for pension and postretirement benefits for the periods indicated:
		Pension Benefits			Postretirement Benefits
		December 31,			December 31,
		2013		2012	2013		2012
	Discount rate	5.25%		4.25%	5.00%		4.00%
	Compensation increase rate	3.35% - 3.40%		3.45% - 3.50%	3.35% - 3.40%		3.45% - 3.50%
	The following table sets forth the weighted-average assumptions used to determine net periodic benefit costs for the periods indicated:
		Years Ended December 31,
		2013		2012	2011
	Discount rate - pension plans	4.25%		5.00%	5.50%
	Discount rate - postretirement plans	4.00%		5.00%	5.50%
	Expected long-term return on plan assets	8.25%		8.25%	8.25%
	Compensation increase rate	3.45% - 3.50%		3.20% - 3.80%	3.30% - 3.90%
Assumed health care cost trend rates	'
	Health Care Cost Trend Rates - The following table sets forth the assumed health care cost-trend rates for the periods indicated:
		2013		2012
	Health care cost-trend rate assumed for next year	4.0% - 8.25%		4.0% - 9.0%
	Rate to which the cost-trend rate is assumed to decline	4.0% - 5.0%		4.0% - 5.0%
	(the ultimate trend rate)
	Year that the rate reaches the ultimate trend rate	2022		2022
Effects of a one percentage point change in assumed health care costs trend rates	'
	Assumed health care cost-trend rates have an impact on the amounts reported for our health care plans.  A one percentage point change in assumed health care cost-trend rates would have the following effects:
		One Percentage			One Percentage
		Point Increase			Point Decrease
		(Thousands of dollars)
	Effect on total of service and interest cost	$	1,136		$	(1,022	)
	Effect on postretirement benefit obligation	$	15,152		$	(14,350	)
Schedule of allocation of plan assets	'
	Plan Assets - Our investment strategy is to invest plan assets in accordance with sound investment practices that emphasize long-term fundamentals.  The goal of this strategy is to maximize investment returns while managing risk in order to meet the plan’s current and projected financial obligations.  The plan’s investments include a diverse blend of various domestic and international equities, investments in various classes of debt securities, insurance contracts and venture capital.  The target allocation for the assets of our pension plan is as follows:
	U.S. large-cap equities	37	%
	Aggregate bonds	24	%
	Developed foreign large-cap equities	10	%
	Alternative investments	8	%
	Mid-cap equities	6	%
	Emerging markets equities	5	%
	Small-cap equities	4	%
	High-yield bonds	3	%
	Developed foreign bonds	2	%
	Emerging market bonds	1	%
	Total	100	%
	As part of our risk management for the plans, minimums and maximums have been set for each of the asset classes listed above. All investment managers for the plan are subject to certain restrictions on the securities they purchase and, with the exception of indexing purposes, are prohibited from owning our stock.
	The following tables set forth our pension benefits and postretirement benefits plan assets by fair value category as of the measurement date:
		Pension Benefits
		31-Dec-13
	Asset Category	Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
	Investments:
	Equity securities (a)	$	680,590		$	60,336		$	—		$	740,926
	Government obligations	—			111,288			—			111,288
	Corporate obligations (b)	—			95,432			—			95,432
	Cash and money market funds (c)	27,699			—			—			27,699
	Insurance and group annuity contracts	—			—			63,458			63,458
	Other investments (d)	—			—			73,946			73,946
	Total assets	$	708,289		$	267,056		$	137,404		$	1,112,749
	(a) - This category represents securities of the respective market sector from diverse industries.
	(b) - This category represents bonds from diverse industries.
	(c) - This category is primarily money market funds.
	(d) - This category represents alternative investments.
		Pension Benefits
		31-Dec-12
	Asset Category	Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
	Investments:
	Equity securities (a)	$	541,539		$	61,242		$	—		$	602,781
	Government obligations	—			116,936			—			116,936
	Corporate obligations (b)	—			104,078			—			104,078
	Cash and money market funds (c)	33,296			—			—			33,296
	Insurance and group annuity contracts	—			—			70,411			70,411
	Other investments (d)	—			—			67,762			67,762
	Total assets	$	574,835		$	282,256		$	138,173		$	995,264
	(a) - This category represents securities of the respective market sector from diverse industries.
	(b) - This category represents bonds from diverse industries.
	(c) - This category is primarily money market funds.
	(d) - This category represents alternative investments.
		Postretirement Benefits
		31-Dec-13
	Asset Category	Level 1			Level 2			Level 3			Total
		(Thousands of dollars)
	Investments:
	Equity securities (a)	$	37,796		$	90		$	—		$	37,886
	Government obligations	—			166			—			166
	Corporate obligations (b)	17,207			142			—			17,349
	Cash and money market funds (c)	13,936			—			—			13,936
	Insurance and group annuity contracts	—			106,189			—			106,189
	Other investments (d)	—			—			109			109
	Total assets	$	68,939		$	106,587		$	109		$	175,635
	(a) - This category represents securities of the respective market sector from diverse industries.
	(b) - This category represents bonds from diverse industries.
	(c) - This category is primarily money market funds.
	(d) - This category represents alternative investments.
		Postretirement Benefits
	31-Dec-12
Asset Category	Level 1			Level 2			Level 3			Total
	(Thousands of dollars)
Investments:
Equity securities (a)	$	21,548		$	140		$	—		$	21,688
Government obligations	—			268			—			268
Corporate obligations (b)	17,522			238			—			17,760
Cash and money market funds (c)	18,311			—			—			18,311
Insurance and group annuity contracts	—			89,979			—			89,979
Other investments (d)	—			—			156			156
Total assets	$	57,381		$	90,625		$	156		$	148,162
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category represents money market funds.
(d) - This category represents alternative investments.
Reconciliation of Level 3 fair value measurements of pension plan	'
	The following tables set forth the reconciliation of Level 3 fair value measurements of our pension plan for the periods indicated:
		Pension Benefits
		31-Dec-13
		Insurance			Other			Total
		and Group			Investments
		Annuity
		Contracts
		(Thousands of dollars)
	1-Jan-13	$	70,411		$	67,762		$	138,173
	Net realized and unrealized gains (losses)	(6,953		)	6,184			(769		)
	31-Dec-13	$	63,458		$	73,946		$	137,404
		Pension Benefits
		31-Dec-12
		Insurance			Other			Total
		and Group			Investments
		Annuity
		Contracts
		(Thousands of dollars)
	1-Jan-12	$	70,818		$	66,243		$	137,061
	Net realized and unrealized gains (losses)	(407		)	1,519			1,112
	31-Dec-12	$	70,411		$	67,762		$	138,173
Pension benefits and postretirement benefit payments expected to be paid	'
	The following table sets forth the pension benefits and postretirement benefits payments expected to be paid in 2014-2023:
		Pension			Postretirement
		Benefits			Benefits
	Benefits to be paid in:	(Thousands of dollars)
	2014	$	63,856		$	16,251
	2015	$	64,588		$	17,135
	2016	$	66,477		$	18,142
	2017	$	68,626		$	19,095
	2018	$	70,873		$	19,875
	2019 through 2023	$	386,366		$	106,346

INCOME_TAXES_Tables

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Provisions for Income Taxes	'
	The following table sets forth our provisions for income taxes for the periods indicated:
		Years Ended December 31,
		2013			2012			2011
	Current income taxes	(Thousands of dollars)
	Federal	$	7,313		$	(16,083	)	$	(32,291	)
	State	4,554			1,798			1,707
	Total current income taxes from continuing operations	11,867			(14,285		)	(30,584		)	(a)
	Deferred income taxes
	Federal	137,654			213,127			228,257
	State	13,861			16,353			28,375
	Total deferred income taxes from continuing operations	151,515			229,480			256,632			(a)
	Total provision for income taxes from continuing operations	163,382			215,195			226,048
	Discontinued operations	—			8,749			1,255
	Total provision for income taxes	$	163,382		$	223,944		$	227,303
	(a) Includes a $37.7 million reclassification from current income taxes to deferred related to revisions of estimated depreciation in our filed tax returns compared with our 2010 tax provision.
Reconciliation of Income Tax Provision	'
	The following table is a reconciliation of our income tax provision from continuing operations for the periods indicated:
		Years Ended December 31,
		2013			2012			2011
		(Thousands of dollars)
	Income from continuing operations before income taxes	$	740,343		$	944,446		$	983,562
	Less: Net income attributable to noncontrolling interest	310,428			382,911			399,150
	Income from continuing operations attributable to ONEOK before	429,915			561,535			584,412
	income taxes
	Federal statutory income tax rate	35		%	35		%	35		%
	Provision for federal income taxes	150,470			196,537			204,543
	State income taxes, net of federal tax benefit	11,970			11,799			20,334
	Other, net	942			6,859			1,171
	Income tax provision from continuing operations	$	163,382		$	215,195		$	226,048
Schedule of Deferred Tax Assets and Liabilities	'
	The following table sets forth the tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities for the periods indicated:
		December 31,			December 31,
		2013			2012
	Deferred tax assets	(Thousands of dollars)
	Employee benefits and other accrued liabilities	$	78,793		$	128,418
	Federal net operating loss	12,484			—
	State net operating loss and benefits	38,322			31,990
	Energy Services capacity release	46,726			—
	Other comprehensive income	78,369			140,802
	Other	20,872			1,446
	Total deferred tax assets	275,566			302,656
	Deferred tax liabilities
	Excess of tax over book depreciation and depletion	822,706			760,211
	Investment in partnerships	1,217,605			969,347
	Regulatory assets	132,676			204,625
	Total deferred tax liabilities	2,172,987			1,934,183
	Net deferred tax liabilities	$	1,897,421		$	1,631,527

UNCONSOLIDATED_AFFILIATES_Tabl

UNCONSOLIDATED AFFILIATES (Tables)	12 Months Ended
	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]	'
Equity Earnings from Investments [Table Text Block]	'
	Equity Earnings from Investments - The following table sets forth our equity earnings from investments for the periods indicated.  All amounts in the table below are equity earnings from investments in our ONEOK Partners segment:
		Years Ended December 31,
		2013				2012				2011
		(Thousands of dollars)
	Northern Border Pipeline	$	65,046			$	72,705			$	76,365
	Overland Pass Pipeline Company	20,461				20,043				19,535
	Fort Union Gas Gathering, L.L.C.	15,826				17,218				15,280
	Bighorn Gas Gathering	1,952				3,820				5,990
	Other	7,232				9,238				10,076
	Equity earnings from investments	$	110,517			$	123,024			$	127,246
Schedule of Equity Method Investments	'
	Investments in Unconsolidated Affiliates - The following table sets forth our investments in unconsolidated affiliates for the periods indicated:
		Net		December 31,				December 31,
		Ownership		2013				2012
		Interest
				(Thousands of dollars)
	Northern Border Pipeline	50%		$	404,803			$	393,317
	Overland Pass Pipeline Company	50%		466,671				468,710
	Fort Union Gas Gathering, L.L.C.	37%		125,220				120,782
	Bighorn Gas Gathering	49%		87,837				90,428
	Other	Various		145,307				148,168
	Investments in unconsolidated affiliates (a)			$	1,229,838			$	1,221,405
	(a) - Equity method goodwill (Note A) was $224.3 million at December 31, 2013 and 2012.
Unconsolidated Affiliates Financial Information	'
	Unconsolidated Affiliates Financial Information - The following tables set forth summarized combined financial information of our unconsolidated affiliates for the periods indicated:
		December 31,				December 31,
		2013				2012
		(Thousands of dollars)
	Balance Sheet
	Current assets	$	155,310			$	175,930
	Property, plant and equipment, net	$	2,557,571			$	2,593,122
	Other noncurrent assets	$	34,478			$	35,005
	Current liabilities	$	98,967			$	145,147
	Long-term debt	$	442,103			$	472,630
	Other noncurrent liabilities	$	58,221			$	42,451
	Accumulated other comprehensive loss	$	(2,291	)		$	(2,503	)
	Owners’ equity	$	2,150,359			$	2,146,332
		Years Ended December 31,
		2013				2012				2011
		(Thousands of dollars)
	Income Statement
	Operating revenues	$	528,665			$	573,197			$	496,158
	Costs and expenses	$	256,292			$	269,858			$	221,261
	Net income	$	248,998			$	279,766			$	249,559
	Distributions paid to us	$	137,498			$	155,741			$	156,385

ONEOK_PARTNERS_Tables

ONEOK PARTNERS (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill [Line Items]	'
Goodwill by Segment	'
	Goodwill - The following table sets forth our goodwill by segment for the periods indicated:
		ONEOK				Natural Gas			Energy			Total
		Partners				Distribution			Services
		(Thousands of dollars)
	31-Dec-12	$	433,535			$	157,953		$	—		$	591,488
	Acquisitions	92,000				—			—			92,000
	31-Dec-13	$	525,535			$	157,953		$	—		$	683,488
Transactions With Related Parties [Table Text Block]	'
	Ownership Interest in ONEOK Partners - Our ownership interest in ONEOK Partners is shown in the table below as of December 31, 2013:
	General partner interest		2	%
	Limited partner interest (a)		39.2	%
	Total ownership interest		41.2	%
Ownership interest in ONEOK Partners	'
	The following table shows ONEOK Partners’ transactions with us for the periods indicated:
			Years Ended December 31,
			2013				2012			2011
			(Thousands of dollars)
	Revenues		$	340,743			$	352,099		$	403,603
	Expenses
	Cost of sales and fuel		$	37,963			$	33,094		$	48,163
	Administrative and general expenses		265,448				246,050			251,239
	Total expenses		$	303,411			$	279,144		$	299,402
ONEOK Partners' Distributions Paid	'
	The following table shows ONEOK Partners’ distributions paid during the periods indicated:
			Years Ended December 31,
			2013				2012			2011
			(Thousands, except per unit amounts)
	Distribution per unit		$	2.87			$	2.59		$	2.325
	General partner distributions		$	18,193			$	15,217		$	12,189
	Incentive distributions		251,664				186,130			123,386
	Distributions to general partner		269,857				201,347			135,575
	Limited partner distributions to ONEOK		266,302				235,442			197,132
	Limited partner distributions to noncontrolling interest		373,554				324,123			276,739
	Total distributions paid		$	909,713			$	760,912		$	609,446
ONEOK Partners' Distributions Declared	'
	The following table shows ONEOK Partners’ distributions declared for the periods indicated:
			Years Ended December 31,
			2013				2012			2011
			(Thousands, except per unit amounts)
	Distribution per unit		$	2.89			$	2.69		$	2.365
	General partner distributions		$	18,625			$	16,355		$	12,515
	Incentive distributions		259,466				210,095			131,212
	Distributions to general partner		278,091				226,450			143,727
	Limited partner distributions to ONEOK		268,157				249,600			200,524
	Limited partner distributions to noncontrolling interest		384,988				341,704			281,500
	Total distributions declared		$	931,236			$	817,754		$	625,751
Oneok Partners [Member]	'
Goodwill [Line Items]	'
Goodwill by Segment	'
	The purchase price and assessment of the fair value of the assets acquired and liabilities assumed were as follows (in thousands):
				Total
	Property, plant and equipment
	Gathering pipelines and related equipment			$	59,174
	Processing and fractionation and related equipment			50,595
	General plant and other			120
	Intangible assets			103,000
	Identifiable assets acquired			212,889
	Goodwill			92,000
	Total purchase price			$	304,889

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Future Minimum Rental Payments for Operating Lease ad Firm Transportation and Storage Contracts	'
	ONEOK	Operating
		Leases
		(Millions of dollars)
	2014	$	3.4
	2015	2.9
	2016	2.5
	2017	2.1
	2018	1.9
	Thereafter	3.3
	Total	$	16.1
	Our former Natural Gas Distribution segment is a party to fixed-price contracts providing it with firm transportation and storage capacity. The costs associated with these contracts are recovered through rates. Future commitments related to these contracts are $900.0 million. These contracts are obligations of ONE Gas as the result of the separation.
	Our Energy Services segment also is a party to fixed-price contracts related to firm transportation and storage that are not being released as part of the wind down process and will expire before April 2014. Future commitments related to these contracts are $11.2 million.
	ONEOK	Operating		Firm		Total
	Partners	Leases		Transportation
				and Storage
				Contracts
		(Millions of dollars)
	2014	$	2	$	18.4	$	20.4
	2015	0.5		16.3		16.8
	2016	0.3		14.4		14.7
	2017	0.2		12.8		13
	2018	0.2		11.9		12.1
	Thereafter	0.7		30.2		30.9
	Total	$	3.9	$	104	$	107.9

SEGMENTS_Tables

SEGMENTS (Tables)	12 Months Ended
	Dec. 31, 2013
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:
	Year Ended December 31, 2013	ONEOK			Natural Gas			Energy			Other and			Total
		Partners (a)			Distribution			Services			Eliminations
		(Thousands of dollars)
	Sales to unaffiliated customers	$	11,528,530		$	1,689,945		$	1,381,636		$	2,606		$	14,602,717
	Intersegment revenues	340,743			7			195,926			(536,676		)	—
	Total revenues	$	11,869,273		$	1,689,952		$	1,577,562		$	(534,070	)	$	14,602,717
	Net margin	$	1,647,060		$	813,008		$	(172,985	)	$	2,600		$	2,289,683
	Operating costs	521,513			444,866			13,133			10,941			990,453
	Depreciation and amortization	236,743			144,758			277			2,599			384,377
	Gain on sale of assets	11,881			—			—			—			11,881
	Operating income	$	900,685		$	223,384		$	(186,395	)	$	(10,940	)	$	926,734
	Equity earnings from investments	$	110,517		$	—		$	—		$	—		$	110,517
	Investments in unconsolidated affiliates	$	1,229,838		$	—		$	—		$	—		$	1,229,838
	Total assets	$	12,862,608		$	3,857,722		$	347,470		$	639,758		$	17,707,558
	Noncontrolling interests in consolidated subsidiaries	$	4,536		$	—		$	—		$	2,502,793		$	2,507,329
	Capital expenditures	$	1,939,326		$	292,080		$	—		$	25,179		$	2,256,585
	(a) - Our ONEOK Partners segment has regulated and nonregulated operations. Our ONEOK Partners segment’s regulated operations had
	revenues of $781.7 million, net margin of $545.0 million and operating income of $281.0 million.
	Year Ended December 31, 2012	ONEOK			Natural Gas			Energy			Other and			Total
		Partners (a)			Distribution			Services			Eliminations
		(Thousands of dollars)
	Sales to unaffiliated customers	$	9,830,052		$	1,379,366		$	1,421,171		$	1,970		$	12,632,559
	Intersegment revenues	352,099			(2,717		)	105,402			(454,784		)	—
	Total revenues	$	10,182,151		$	1,376,649		$	1,526,573		$	(452,814	)	$	12,632,559
	Net margin	$	1,641,832		$	756,389		$	(49,344	)	$	1,964		$	2,350,841
	Operating costs	482,540			410,572			17,950			(2,084		)	908,978
	Depreciation and amortization	203,101			130,150			361			2,232			335,844
	Goodwill impairment	—			—			10,255			—			10,255
	Gain on sale of assets	6,736			—			—			—			6,736
	Operating income	$	962,927		$	215,667		$	(77,910	)	$	1,816		$	1,102,500
	Equity earnings from investments	$	123,024		$	—		$	—		$	—		$	123,024
	Investments in unconsolidated affiliates	$	1,221,405		$	—		$	—		$	—		$	1,221,405
	Total assets	$	10,959,230		$	3,535,489		$	493,006		$	867,550		$	15,855,275
	Noncontrolling interests in consolidated subsidiaries	$	4,767		$	—		$	—		$	2,098,074		$	2,102,841
	Capital expenditures	$	1,560,513		$	280,294		$	—		$	25,346		$	1,866,153
	(a) - Our ONEOK Partners segment has regulated and non-regulated operations. Our ONEOK Partners segment’s regulated operations had
	revenues of $722.1 million, net margin of $618.0 million and operating income of $375.6 million.
	Year Ended December 31, 2011	ONEOK			Natural Gas			Energy			Other and			Total
		Partners (a)			Distribution			Services			Eliminations
		(Thousands of dollars)
	Sales to unaffiliated customers	$	10,919,004		$	1,609,628		$	2,274,799		$	2,363		$	14,805,794
	Intersegment revenues	403,603			11,706			502,418			(917,727		)	—
	Total revenues	$	11,322,607		$	1,621,334		$	2,777,217		$	(915,364	)	$	14,805,794
	Net margin	$	1,577,380		$	751,835		$	48,740		$	2,404		$	2,380,359
	Operating costs	459,364			422,073			24,527			2,359			908,323
	Depreciation and amortization	177,549			132,212			445			1,954			312,160
	Loss on sale of assets	(963		)	—			—			—			(963		)
	Operating income	939,504			197,550			23,768			(1,909		)	1,158,913
	Equity earnings from investments	$	127,246		$	—		$	—		$	—		$	127,246
	Investments in unconsolidated affiliates	$	1,223,398		$	—		$	—		$	—		$	1,223,398
	Total assets	$	8,946,676		$	3,392,475		$	562,728		$	794,756		$	13,696,635
	Noncontrolling interests in consolidated subsidiaries	$	5,112		$	—		$	—		$	1,556,047		$	1,561,159
	Capital expenditures	$	1,063,383		$	242,590		$	41		$	30,053		$	1,336,067
	(a) - Our ONEOK Partners segment has regulated and non-regulated operations. Our ONEOK Partners segment’s regulated operations had
	revenues of $658.5 million, net margin of $469.0 million and operating income of $232.8 million.

QUARTERLY_FINANCIAL_DATA_UNAUD1

QUARTERLY FINANCIAL DATA (UNAUDITED) (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Quarterly financial disclosure	'
		First		Second		Third		Fourth
	Year Ended December 31, 2013	Quarter		Quarter		Quarter		Quarter
		(Thousands of dollars except per share amounts)
	Total revenues	$	3,541,445	$	3,349,236	$	3,571,925	$	4,140,111
	Net margin	$	623,452	$	453,389	$	561,188	$	651,654
	Income from continuing operations	$	165,705	$	79,495	$	147,698	$	184,063
	Net income	$	165,705	$	79,495	$	147,698	$	184,063
	Net income attributable to ONEOK	$	112,521	$	919	$	62,356	$	90,737
	Earnings per share total
	Basic	$	0.55	$	—	$	0.3	$	0.44
	Diluted	$	0.54	$	—	$	0.3	$	0.43
		First		Second		Third		Fourth
	Year Ended December 31, 2012	Quarter		Quarter		Quarter		Quarter
		(Thousands of dollars except per share amounts)
	Total revenues	$	3,414,600	$	2,529,260	$	3,028,775	$	3,659,924
	Net margin	$	643,587	$	548,962	$	553,972	$	604,320
	Income from continuing operations	$	219,450	$	148,938	$	164,988	$	195,875
	Income from discontinued operations and gain on sale,	$	14,012	$	267	$	—	$	—
	net of tax
	Net income	$	233,462	$	149,205	$	164,988	$	195,875
	Net income attributable to ONEOK	$	122,865	$	60,993	$	65,219	$	111,542
	Earnings per share total
	Basic	$	0.59	$	0.29	$	0.32	$	0.55
	Diluted	$	0.58	$	0.29	$	0.31	$	0.53

SUBSEQUENT_EVENTS_Tables

SUBSEQUENT EVENTS (Tables) (ONE Gas [Member])	3 Months Ended
	Mar. 31, 2014
ONE Gas [Member]	'
Debt Instrument [Line Items]	'
Schedule of Long-term Debt Instruments [Table Text Block]	'
	The following table details information about each of the three series of Senior Notes:
		(In millions)
	2.07% notes due February 1, 2019	$	300
	3.61% notes due February 1, 2024	300
	4.658% notes due February 1, 2044	600
		$	1,200

SUMMARY_OF_SIGNIFICANT_ACCOUNT2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
		Y
Entity [Line Items]	'	'	'	'
Noncash charges	$10,200,000	'	'	'
Ownership interest	'	41.20%	43.40%	42.80%
Goodwill, Impairment Loss	'	0	10,255,000	0
Equity Method Investments	1,229,838,000	1,229,838,000	1,221,405,000	1,223,398,000
Equity method goodwill	224,300,000	224,300,000	'	'
Reportable business segments	'	3	'	'
Number of natural gas distribution services customers	2,000,000	2,000,000	'	'
Regulatory assets	383,600,000	383,600,000	585,000,000	'
Time period regulatory assets are being recovered (in years)	'	25	'	'
Number of years of service employees must work to be entitled to postretirement medical and life insurance benefits (in years)	'	5	'	'
Bighorn Gas Gathering LLC [Member]	'	'	'	'
Entity [Line Items]	'	'	'	'
Net ownership percentage	49.00%	49.00%	'	'
Equity Method Investments	87,837,000	87,837,000	90,428,000	'
Equity method goodwill	53,400,000	53,400,000	'	'
Other Powder River Basin Investments [Member]	'	'	'	'
Entity [Line Items]	'	'	'	'
Equity Method Investments	204,000,000	204,000,000	'	'
Equity method goodwill	130,000,000	130,000,000	'	'
Natural Gas Distribution [Member]	'	'	'	'
Entity [Line Items]	'	'	'	'
Goodwill, Impairment Loss	'	'	0	'
Equity Method Investments	0	0	0	0
Regulatory assets	376,800,000	376,800,000	577,100,000	'
Pension Costs [Member] | Natural Gas Distribution [Member]	'	'	'	'
Entity [Line Items]	'	'	'	'
Regulatory assets	$341,100,000	$341,100,000	$499,400,000	'

EXIT_ACTIVITIES_Details

EXIT ACTIVITIES (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	MMcf
Restructuring Cost and Reserve [Line Items]	'	'	'
Assigned storage capacity	18,000	'	'
Noncash charges	$138,600,000	$0	'
Settlements of business exit costs	-17,700,000	'	'
Accretion	1,100,000	'	'
Charges attributable to exit activities, net of settlements	121,971,000	0	0
Expected future noncash charge	1,700,000	'	'
Expected future cash payments associated with released transportation and storage capacity from the wind-down of our Energy Services segment	80,000,000	'	'
2014 [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Expected future cash payments associated with released transportation and storage capacity from the wind-down of our Energy Services segment	33,000,000	'	'
2015 [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Expected future cash payments associated with released transportation and storage capacity from the wind-down of our Energy Services segment	24,000,000	'	'
2016 [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Expected future cash payments associated with released transportation and storage capacity from the wind-down of our Energy Services segment	13,000,000	'	'
2017 - 2023 [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Expected future cash payments associated with released transportation and storage capacity from the wind-down of our Energy Services segment	$10,000,000	'	'

DISCONTINUED_OPERATIONS_Detail

DISCONTINUED OPERATIONS (Details) (USD $)	1 Months Ended	12 Months Ended
	Jan. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'
Proceeds from Divestiture of Businesses and Interests in Affiliates	'	$32,900,000	'	'
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	'	0	13,517,000	0
Gain on sale of business, tax impact	'	8,300,000	'	'
Description and timing of discontinued operations	'	'On February 1, 2012, we sold ONEOK Energy Marketing Company, our Natural Gas Distribution segmentbs retail natural gas marketing business, to Constellation Energy Group, Inc. for $22.5 million plus working capital.	'	'
Revenues	27,607,000	'	'	313,371,000
Cost of sales and fuel	25,961,000	'	'	302,561,000
Net margin	1,646,000	'	'	10,810,000
Operating costs	408,000	'	'	7,147,000
Depreciation and amortization	8,000	'	'	128,000
Operating income	1,230,000	'	'	3,535,000
Other income (expense), net	0	'	'	-50,000
Income taxes	-468,000	0	-8,749,000	-1,255,000
Income from discontinued operations, net	$762,000	'	'	$2,230,000

FAIR_VALUE_MEASUREMENTS_Part_1

FAIR VALUE MEASUREMENTS - Part 1 (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Commodity contracts	'	'
Cash collateral held	$0	$17,700,000
Cash collateral posted	15,700,000	4,500,000
Fair Value, Measurements, Recurring [Member]	'	'
Commodity contracts	'	'
Financial contracts	5,368,000	36,242,000
Physical contracts	611,000	3,964,000
Interest-rate contracts	54,503,000	10,923,000
Total derivatives	60,482,000	51,129,000
Trading securities	'	5,978,000
Fair value of firm commitments	599,000	'
Available-for-sale investment securities	1,569,000	2,027,000
Total assets	62,650,000	59,134,000
Commodity contracts	'	'
Financial contracts	-1,068,000	-10,208,000
Physical contracts	-2,964,000	-128,000
Total derivatives	'	-10,336,000
Fair value of firm commitments	'	-1,280,000
Total liabilities	-4,032,000	-11,616,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Commodity contracts	'	'
Financial contracts	4,477,000	69,957,000
Physical contracts	0	0
Interest-rate contracts	0	0
Total derivatives	4,477,000	69,957,000
Trading securities	'	5,978,000
Fair value of firm commitments	0	'
Available-for-sale investment securities	1,569,000	2,027,000
Total assets	6,046,000	77,962,000
Commodity contracts	'	'
Financial contracts	-7,624,000	-35,172,000
Physical contracts	0	0
Total derivatives	'	-35,172,000
Fair value of firm commitments	'	0
Total liabilities	-7,624,000	-35,172,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Commodity contracts	'	'
Financial contracts	647,000	10,780,000
Physical contracts	4,000	2,083,000
Interest-rate contracts	54,503,000	10,923,000
Total derivatives	55,154,000	23,786,000
Trading securities	'	0
Fair value of firm commitments	0	'
Available-for-sale investment securities	0	0
Total assets	55,154,000	23,786,000
Commodity contracts	'	'
Financial contracts	-776,000	-1,737,000
Physical contracts	-4,000	0
Total derivatives	'	-1,737,000
Fair value of firm commitments	'	0
Total liabilities	-780,000	-1,737,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Commodity contracts	'	'
Financial contracts	3,094,000	7,107,000
Physical contracts	1,764,000	2,032,000
Interest-rate contracts	0	0
Total derivatives	4,858,000	9,139,000
Trading securities	'	0
Fair value of firm commitments	599,000	'
Available-for-sale investment securities	0	0
Total assets	5,457,000	9,139,000
Commodity contracts	'	'
Financial contracts	-3,435,000	-7,177,000
Physical contracts	-4,117,000	-279,000
Total derivatives	'	-7,456,000
Fair value of firm commitments	'	-1,280,000
Total liabilities	-7,552,000	-8,736,000
Fair Value, Measurements, Recurring [Member] | Netting and Collateral [Member]	'	'
Commodity contracts	'	'
Financial contracts	-2,850,000	-51,602,000
Physical contracts	-1,157,000	-151,000
Interest-rate contracts	0	0
Total derivatives	-4,007,000	-51,753,000
Trading securities	'	0
Fair value of firm commitments	0	'
Available-for-sale investment securities	0	0
Total assets	-4,007,000	-51,753,000
Commodity contracts	'	'
Financial contracts	10,767,000	33,878,000
Physical contracts	1,157,000	151,000
Total derivatives	'	34,029,000
Fair value of firm commitments	'	0
Total liabilities	11,924,000	34,029,000
Fair Value, Measurements, Recurring [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'
Commodity contracts	'	'
Financial contracts	8,218,000	87,844,000
Physical contracts	1,768,000	4,115,000
Interest-rate contracts	54,503,000	10,923,000
Total derivatives	64,489,000	102,882,000
Trading securities	'	5,978,000
Fair value of firm commitments	599,000	'
Available-for-sale investment securities	1,569,000	2,027,000
Total assets	66,657,000	110,887,000
Commodity contracts	'	'
Financial contracts	-11,835,000	-44,086,000
Physical contracts	-4,121,000	-279,000
Total derivatives	'	-44,365,000
Fair value of firm commitments	'	-1,280,000
Total liabilities	($15,956,000)	($45,645,000)

FAIR_VALUE_MEASUREMENTS_FAIR_V

FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS - Part 2 (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets And Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Balance, beginning	$403	$17,821
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities still held as of December 31	-134	1,859
Included in earnings	-3,748	-7,500
Included in other comprehensive income (loss)	800	-5,587
Transfers into Level 3	'	-3,636
Transfers out of Level 3	'	-695
Settlements	450	'
Balance, ending	-2,095	403
Derivative Financial Instruments, Assets Liabilities [Member]	'	'
Fair Value, Assets And Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Balance, beginning	1,683	25,104
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities still held as of December 31	-804	1,971
Included in earnings	-5,627	-13,503
Included in other comprehensive income (loss)	800	-5,587
Transfers into Level 3	'	-3,636
Transfers out of Level 3	'	-695
Settlements	450	'
Balance, ending	-2,694	1,683
Firm Commitments [Member]	'	'
Fair Value, Assets And Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Balance, beginning	-1,280	-7,283
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities still held as of December 31	670	-112
Included in earnings	1,879	6,003
Included in other comprehensive income (loss)	0	0
Transfers into Level 3	'	0
Transfers out of Level 3	'	0
Settlements	0	'
Balance, ending	$599	($1,280)

FAIR_VALUE_MEASUREMENTS_FAIR_V1

FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS - Part 3 (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Estimate of Fair Value, Fair Value Disclosure [Member]	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Long-term debt, including current maturities, fair value	$8,200,000,000	$7,500,000,000
Carrying (Reported) Amount, Fair Value Disclosure [Member]	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Long-term debt, including current maturities, carrying value	$7,800,000,000	$6,500,000,000

RISK_MANAGEMENT_AND_HEDGING_AC2

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES - Part 1 (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	$64,489,000	$102,882,000
(Liabilities)	'	-15,956,000	-44,365,000
Inventory cash flow hedges derivative assets	'	5,800,000	16,900,000
Designated as Hedging Instrument [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	63,578,000	58,495,000
(Liabilities)	'	-14,036,000	-5,011,000
Not Designated as Hedging Instrument [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	911,000	44,387,000
(Liabilities)	'	-1,920,000	-39,354,000
Commodity Contract [Member] | Designated as Hedging Instrument [Member] | Financial Derivative Instrument [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	8,011,000	47,516,000
(Liabilities)	'	-10,573,000	-4,885,000
Commodity Contract [Member] | Designated as Hedging Instrument [Member] | Physical Derivative Instrument [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	1,064,000	56,000
(Liabilities)	'	-3,463,000	-126,000
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member] | Financial Derivative Instrument [Member] | Non Trading [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	202,000	24,970,000
(Liabilities)	'	-1,262,000	-25,009,000
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member] | Financial Derivative Instrument [Member] | Trading [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	5,000	15,358,000
(Liabilities)	'	0	-14,192,000
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member] | Physical Derivative Instrument [Member] | Non Trading [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	704,000	4,059,000
(Liabilities)	'	-658,000	-153,000
Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Assets	'	54,503,000	10,923,000
(Liabilities)	'	0	0
Cash Flow Hedging [Member] | Forward Starting Interest Rate Swap [Member] | Oneok Partners [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Notional Amount Of Cash Flow Hedge Instruments Greater Than 12 Months	'	400,000,000	400,000,000
Notional Amount Of Cash Flow Hedge Instruments Less Than 12 Months	$500,000,000	'	'

RISK_MANAGEMENT_AND_HEDGING_AC3

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES - Part 2 (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified	MMcf	MMcf
Fixed Price [Member] | Natural Gas [Member] | Cash Flow Hedging [Member] | Sold [Member] | Exchange Futures [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-65,000	-85,100
Fixed Price [Member] | Natural Gas [Member] | Cash Flow Hedging [Member] | Purchased [Member] | Exchange Futures [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0	0
Fixed Price [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Sold [Member] | Options [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0	-100,800
Fixed Price [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Sold [Member] | Exchange Futures [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-9,700	-60,400
Fixed Price [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Purchased [Member] | Options [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0	102,100
Fixed Price [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Purchased [Member] | Exchange Futures [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	5,800	60,700
Fixed Price [Member] | Crude oil and NGLs [Member] | Cash Flow Hedging [Member] | Sold [Member] | Swaps [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-4	-1.1
Fixed Price [Member] | Crude oil and NGLs [Member] | Cash Flow Hedging [Member] | Purchased [Member] | Swaps [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0	0
Fixed Price [Member] | Crude oil and NGLs [Member] | Not Designated as Hedging Instrument [Member] | Sold [Member] | Exchange Futures [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-0.3	0
Fixed Price [Member] | Crude oil and NGLs [Member] | Not Designated as Hedging Instrument [Member] | Purchased [Member] | Exchange Futures [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0.3	0
Basis [Member] | Natural Gas [Member] | Cash Flow Hedging [Member] | Sold [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-57,400	-56,300
Basis [Member] | Natural Gas [Member] | Cash Flow Hedging [Member] | Purchased [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0	0
Basis [Member] | Natural Gas [Member] | Fair Value Hedging [Member] | Sold [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-1,100	-59,100
Basis [Member] | Natural Gas [Member] | Fair Value Hedging [Member] | Purchased [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	1,100	59,100
Basis [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Sold [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	-11,200	-81,700
Basis [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Purchased [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	8,500	80,200
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Sold [Member] | Forward Starting Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount of cash flow hedge instruments	0	0
Interest Rate Contract [Member] | Cash Flow Hedging [Member] | Purchased [Member] | Forward Starting Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount of cash flow hedge instruments	400	400
Index [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Sold [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	0	-22,300
Index [Member] | Natural Gas [Member] | Not Designated as Hedging Instrument [Member] | Purchased [Member] | Forward and Swaps Contracts [Member]	'	'
Derivative [Line Items]	'	'
Notional amount	1,800	20,300

RISK_MANAGEMENT_AND_HEDGING_AC4

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES - Part 3 (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Gain (Loss) on Discontinuation of Interest Rate Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	$0	$0	$0
Total gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion)	8,842,000	16,709,000	'
Net unrealized gain (loss) in accumulated other comprehensive income (loss)	-5,800,000	'	'
Amount recognized in the next 12 months	-7,000,000	'	'
Amount recognized after the next 12 months	1,200,000	'	'
Losses associated with the change in value of natural gas contracts held deferred in other current assets	4,500,000	5,900,000	14,500,000
Gains (losses) related to the change in fair value of derivatives	-1,400,000	400,000	14,600,000
Change in fair value of the related hedged firm commitments for transportation contracts	1,600,000	500,000	-13,800,000
Not Designated as Hedging Instrument [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivative Instruments, Gain (Loss) Recognized in Income, Net	-4,317,000	8,369,000	17,974,000
Fair value of natural gas call options held	8,700,000	1,800,000	'
Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income on derivatives (effective portion)	-9,831,000	59,826,000	137,739,000
Total gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion)	31,183,000	33,427,000	-11,158,000
Adjustment to natural gas inventory at the lower of cost or market value.	'	'	91,100,000
Cash Flow Hedge Gain Reclassified to Earnings	8,000,000	'	91,100,000
Fair Value Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Interest expense savings from the amortization of terminated swaps	1,700,000	1,700,000	4,300,000
Cost of Sales [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Adjustment to natural gas inventory at the lower of cost or market value.	10,100,000	'	'
Losses related to financial hedging contracts recognized in net margin	'	29,900,000	'
Commodity Contract [Member] | Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Total gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion)	-15,433,000	62,898,000	117,508,000
Commodity Contract [Member] | Sales [Member] | Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income on derivatives (effective portion)	19,049,000	140,862,000	48,601,000
Commodity Contract [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income on derivatives (effective portion)	-14,320,000	-73,881,000	89,618,000
Interest Rate Contract [Member] | Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	-5,300,000	'	'
Total gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion)	46,616,000	-29,471,000	-128,666,000
Amount of accumulated other comprehensive income (loss) attributable primarily to settled interest-rate swaps.	-49,600,000	'	'
Interest Rate Contract [Member] | Interest Expense [Member] | Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income on derivatives (effective portion)	-14,560,000	-7,155,000	-480,000
Trading [Member] | Commodity Contract [Member] | Sales [Member] | Not Designated as Hedging Instrument [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivative Instruments, Gain (Loss) Recognized in Income, Net	-2,051,000	2,413,000	1,796,000
Non Trading [Member] | Commodity Contract [Member] | Cost of Sales [Member] | Not Designated as Hedging Instrument [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivative Instruments, Gain (Loss) Recognized in Income, Net	-2,266,000	5,956,000	16,178,000
Non Trading [Member] | Commodity Contract [Member] | Cost of Sales [Member] | Recently dedesignated [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Total gain (loss) recognized in income on derivatives	$2,200,000	'	'

RISK_MANAGEMENT_AND_HEDGING_AC5

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES - Part 4 (Details) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Derivative Credit Exposure [Line Items]	'
Fair value of collateral	$1.10

PROPERTY_PLANT_AND_EQUIPMENT_P

PROPERTY, PLANT AND EQUIPMENT - Part 1 (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'
Construction in Progress Expenditures Incurred but Not yet Paid	$237,200,000	$228,500,000	$155,700,000
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	15,536,156,000	13,088,991,000	'
Accumulated Depreciation	-3,238,652,000	-2,974,651,000	'
Net property, plant and equipment	12,297,504,000	10,114,340,000	'
Non-Regulated Property, Plant and Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Accumulated Depreciation	-1,112,192,000	-954,398,000	'
Non-Regulated Property, Plant and Equipment [Member] | Gathering pipelines and related equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	2,173,271,000	1,638,037,000	'
Non-Regulated Property, Plant and Equipment [Member] | Processing and fractionation and related equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	2,295,983,000	1,625,146,000	'
Non-Regulated Property, Plant and Equipment [Member] | Storage and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	362,704,000	335,237,000	'
Non-Regulated Property, Plant and Equipment [Member] | Transmission Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	302,718,000	311,038,000	'
Non-Regulated Property, Plant and Equipment [Member] | General plant and other [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	402,523,000	348,636,000	'
Non-Regulated Property, Plant and Equipment [Member] | Construction Work in Process [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	1,112,182,000	881,788,000	'
Regulated Property Plant and Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Accumulated Depreciation	-2,126,460,000	-2,020,253,000	'
Regulated Property Plant and Equipment [Member] | ONEOK Partners [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Average depreciation rates, minimum	2.00%	1.90%	1.90%
Average depreciation rates, maximum	2.20%	2.20%	2.20%
Regulated Property Plant and Equipment [Member] | Natural Gas Distribution [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Average depreciation rates, minimum	2.00%	2.00%	2.00%
Average depreciation rates, maximum	3.00%	3.00%	2.90%
Regulated Property Plant and Equipment [Member] | Storage and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	135,922,000	136,938,000	'
Regulated Property Plant and Equipment [Member] | General plant and other [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	324,703,000	309,119,000	'
Regulated Property Plant and Equipment [Member] | Construction Work in Process [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	822,537,000	703,198,000	'
Regulated Property Plant and Equipment [Member] | Natural Gas Distribution Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	3,703,593,000	3,512,660,000	'
Regulated Property Plant and Equipment [Member] | Natural Gas Transmission Pipelines and Regulated Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	1,850,559,000	1,796,683,000	'
Regulated Property Plant and Equipment [Member] | Natural Gas Liquids Transmission Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Property, plant and equipment	$2,049,461,000	$1,490,511,000	'
Minimum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Gathering pipelines and related equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'5 years	'	'
Minimum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Processing and fractionation and related equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'5 years	'	'
Minimum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Storage and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'5 years	'	'
Minimum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Transmission Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'22 years	'	'
Minimum [Member] | Non-Regulated Property, Plant and Equipment [Member] | General plant and other [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'2 years	'	'
Minimum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Construction Work in Process [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'0 years	'	'
Minimum [Member] | Regulated Property Plant and Equipment [Member] | Storage and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'5 years	'	'
Minimum [Member] | Regulated Property Plant and Equipment [Member] | General plant and other [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'2 years	'	'
Minimum [Member] | Regulated Property Plant and Equipment [Member] | Construction Work in Process [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'0 years	'	'
Minimum [Member] | Regulated Property Plant and Equipment [Member] | Natural Gas Distribution Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'15 years	'	'
Minimum [Member] | Regulated Property Plant and Equipment [Member] | Natural Gas Transmission Pipelines and Regulated Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'5 years	'	'
Minimum [Member] | Regulated Property Plant and Equipment [Member] | Natural Gas Liquids Transmission Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'5 years	'	'
Maximum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Gathering pipelines and related equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'40 years	'	'
Maximum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Processing and fractionation and related equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'40 years	'	'
Maximum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Storage and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'54 years	'	'
Maximum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Transmission Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'54 years	'	'
Maximum [Member] | Non-Regulated Property, Plant and Equipment [Member] | General plant and other [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'60 years	'	'
Maximum [Member] | Non-Regulated Property, Plant and Equipment [Member] | Construction Work in Process [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'0 years	'	'
Maximum [Member] | Regulated Property Plant and Equipment [Member] | Storage and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'54 years	'	'
Maximum [Member] | Regulated Property Plant and Equipment [Member] | General plant and other [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'85 years	'	'
Maximum [Member] | Regulated Property Plant and Equipment [Member] | Construction Work in Process [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'0 years	'	'
Maximum [Member] | Regulated Property Plant and Equipment [Member] | Natural Gas Distribution Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'80 years	'	'
Maximum [Member] | Regulated Property Plant and Equipment [Member] | Natural Gas Transmission Pipelines and Regulated Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'77 years	'	'
Maximum [Member] | Regulated Property Plant and Equipment [Member] | Natural Gas Liquids Transmission Pipelines and Related Equipment [Member]	'	'	'
Property, plant and equipment by type [Abstract]	'	'	'
Estimated Useful Lives	'80 years	'	'

GOODWILL_AND_INTANGIBLE_ASSETS2

GOODWILL AND INTANGIBLE ASSETS (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]	'	'	'
Goodwill, Impairment Loss	$0	$10,255,000	$0
Goodwill	683,488,000	591,488,000	'
Acquisitions	92,000,000	'	'
Amortization expense for intangible assets	8,700,000	7,700,000	7,700,000
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	103,000,000	'	'
Gross Intangible Assets	565,215,000	462,214,000	'
Accumulated Amortization	-66,188,000	-57,496,000	'
Net Intangible Assets	499,027,000	404,718,000	'
Future amortization expense for next five years [Abstract]	'	'	'
Future amortization expense, year one	11,300,000	'	'
Future amortization expense, year two	11,300,000	'	'
Future amortization expense, year three	11,300,000	'	'
Future amortization expense, year four	11,300,000	'	'
Future amortization expense, year five	11,300,000	'	'
Energy Services [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Goodwill, Impairment Loss	'	10,255,000	'
Goodwill	0	0	'
Acquisitions	0	'	'
Natural Gas Distribution [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Goodwill, Impairment Loss	'	0	'
Goodwill	157,953,000	157,953,000	'
Acquisitions	0	'	'
Oneok Partners [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Goodwill, Impairment Loss	'	0	'
Goodwill	525,535,000	433,535,000	'
Acquisitions	92,000,000	'	'
Net Intangible Assets	$343,500,000	$249,200,000	'
Minimum [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Finite-Lived Intangible Asset, Useful Life	'20 years	'	'
Maximum [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Finite-Lived Intangible Asset, Useful Life	'40 years	'	'

CREDIT_FACILITIES_AND_SHORTTER1

CREDIT FACILITIES AND SHORT-TERM NOTES PAYABLE (Details) (USD $)	12 Months Ended				12 Months Ended			12 Months Ended
	Dec. 31, 2014	Jan. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Jan. 31, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2014	Jan. 31, 2014
	ONEOK Credit Agreement [Member]	ONEOK Credit Agreement [Member]	ONEOK Credit Agreement [Member]	ONEOK Credit Agreement [Member]	Partnership 2014 Credit Agreement [Member]	Partnership 2014 Credit Agreement [Member]	Partnership 2014 Credit Agreement [Member]	Partnership Credit Agreement [Member]	ONE Gas credit agreement [Member]	ONE Gas credit agreement [Member]
Line of Credit Facility [Line Items]	'	'	'	'	'	'	'	'	'	'
Interest Rate Description	'Borrowings, if any, will accrue at LIBOR plus 125 basis points	'	'	'	'Borrowings, if any, will accrue at LIBOR plus 117.5 basis points.	'	'	'Borrowings, if any, will accrue at LIBOR plus 130 basis points.	'Borrowings, if any, will accrue at LIBOR plus 79.5 basis points	'
Line of credit facility annual fee description	'Annual facility fee is 25 basis points	'	'	'	'Annual facility fee is 20 basis points based on our current credit rating.	'	'	'Annual facility fee is 20 basis points based on our current credit rating.	'Annual facility fee is 8 basis points	'
Maximum debt-to-capital ratio (in hundredths)	'	'	67.50%	'	'	'	'	'	'	70.00%
Current debt-to-capital ratio	'	'	48.30%	'	'	'	'	'	'	'
Commercial paper	'	'	$564,500,000	'	'	'	'	$0	'	'
Weighted-average interest rate on short-term debt outstanding (in hundredths)	'	'	0.39%	0.46%	'	'	'	'	'	'
Letters of credit issued	'	'	2,200,000	'	'	'	'	0	'	'
Indebtedness To Adjusted Ebitda Maximum	'	4	'	'	'	'	5	'	'	'
Indebtedness To Adjusted Ebitda From Acquisitions Maximum	'	'	'	'	'	'	5.5	'	'	'
Indebtedness To Adjusted Ebitda Current	'	'	'	'	'	'	4	'	'	'
Acquisition price threshold for increase in permitted debt to EBITDA covenant ratio	'	'	'	'	'	'	25,000,000	'	'	'
Partnership Credit Agreement sublimit for issuance of standby letters of credit	'	50,000,000	'	'	'	100,000,000	'	'	'	50,000,000
Line of credit facility swingline subfacility	'	50,000,000	'	'	'	150,000,000	'	'	'	'
Maximum borrowing capacity	'	300,000,000	1,200,000,000	'	'	1,700,000,000	'	1,200,000,000	'	700,000,000
Option to increase borrowing capacity	'	500,000,000	'	'	'	2,400,000,000	'	'	'	1,200,000,000
Short-term Bank Loans and Notes Payable	'	'	'	'	'	'	'	$0	'	'

LONGTERM_DEBT_Details

LONG-TERM DEBT (Details) (USD $)

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2012

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

Oneok [Member]

ONE Gas [Member]

ONE Gas [Member]

ONE Gas [Member]

ONE Gas [Member]

ONE Gas [Member]

Guardian Pipeline [Member]

Guardian Pipeline [Member]

Guardian Pipeline [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Notes Payables due 2012 [Member]

Notes Payables due 2012 [Member]

Senior Notes [Member]

Senior Notes [Member]

Notes Payables due 2015 [Member]

Notes Payables due 2015 [Member]

Notes Payables due 2015 [Member]

Note Payable from Public Offering Due 2022 [Member]

Note Payable from Public Offering Due 2022 [Member]

Note Payable from Public Offering Due 2022 [Member]

Notes Payables due 2035 [Member]

Notes Payables due 2035 [Member]

Other Long Term Debt [Member]

Other Long Term Debt [Member]

Note Payables 1 due 2028 [Member]

Note Payables 1 due 2028 [Member]

Note Payables 2 due 2028 [Member]

Note Payables 2 due 2028 [Member]

Note Payables 2 due 2028 [Member]

Note Payables due 2024 [Member]

Note Payables due 2044 [Member]

Notes Payables 1 due 2022 [Member]

Notes Payables 1 due 2022 [Member]

Note Payable from Public Offering Due 2023 [Member]

Note Payable from Public Offering Due 2023 [Member]

Note Payable from Public Offering Due 2043 [Member]

Note Payable from Public Offering Due 2043 [Member]

Notes Payables due 2019 [Member]

Notes Payables due 2019 [Member]

Note Payable from Public Offering Due 2016 [Member]

Note Payable from Public Offering Due 2016 [Member]

Notes Payable due 2016 [Member]

Notes Payable due 2016 [Member]

Note Payable from Public Offering Due 2017 [Member]

Note Payable from Public Offering Due 2017 [Member]

Notes Payables due 2012 [Member]

Notes Payable due 2011 [Member]

Note Payable from Public Offering Due 2022 [Member]

Note Payable from Public Offering Due 2022 [Member]

Notes Payables due 2036 [Member]

Notes Payables due 2036 [Member]

Notes Payables due 2037 [Member]

Notes Payables due 2037 [Member]

Note Payable from Public Offering Due 2041 [Member]

Note Payable from Public Offering Due 2041 [Member]

Note Payable from Public Offering Due 2018 [Member]

Note Payable from Public Offering Due 2018 [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Partnership Interest [Member]

Note Payable from Public Offering Due 2017 [Member]

Debt Instrument [Line Items]

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Debt Instrument, Maturity Date

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30-Sep-22

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1-Apr-12

15-Mar-11

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1-Apr-12

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Long-term Debt, Gross

$7,756,180,000

$6,514,047,000

$1,688,972,000

$1,689,190,000

'

$400,000,000

$400,000,000

'

$700,000,000

$700,000,000

$400,000,000

$400,000,000

$1,323,000

$1,528,000

$87,649,000

$87,662,000

$100,000,000

$100,000,000

'

$1,200,000,000

$300,000,000

$300,000,000

$600,000,000

'

$67,208,000

$74,857,000

$6,067,208,000

$4,824,857,000

$425,000,000

$0

$400,000,000

$0

$500,000,000

$500,000,000

$650,000,000

$650,000,000

$450,000,000

$450,000,000

$400,000,000

$400,000,000

$350,000,000

'

$900,000,000

$900,000,000

$600,000,000

$600,000,000

$600,000,000

$600,000,000

$650,000,000

$650,000,000

$425,000,000

$0

$350,000,000

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Long-term Debt, Weighted Average Interest Rate

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7.85%

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Interest Rate (in hundredths)

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5.20%

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4.25%

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6.00%

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6.50%

'

6.88%

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2.07%

3.61%

4.66%

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5.00%

'

6.20%

'

8.63%

'

3.25%

'

6.15%

'

2.00%

'

5.90%

'

3.38%

'

6.65%

'

6.85%

'

6.13%

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3.20%

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5.90%

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Unamortized portion of terminated swaps

25,340,000

27,058,000

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Unamortized debt discount

-15,889,000

-14,878,000

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Current maturities

-10,656,000

-10,855,000

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Debt instrument call feature

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'ONEOK may redeem the senior notes due 2015, 2028 (6.875 percent) and 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the senior notes due 2028 (6.5 percent), in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest.B B ONEOK may redeem the remaining balance of its 4.25-percent senior notes due 2022 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three months before the maturity date.B B Prior to this date, ONEOK may redeem these senior notes on the same basis as its other senior notes due 2015, 2028 (6.875 percent) and 2035.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOKbs senior notes due 2015, 2022, 2028 and 2035 are senior unsecured obligations, ranking equally in right of payment with all of ONEOKbs existing and future unsecured senior indebtedness.

'

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'ONEOK may redeem the senior notes due 2015, 2028 (6.875 percent) and 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the senior notes due 2028 (6.5 percent), in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest.B B ONEOK may redeem the remaining balance of its 4.25-percent senior notes due 2022 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three months before the maturity date.B B Prior to this date, ONEOK may redeem these senior notes on the same basis as its other senior notes due 2015, 2028 (6.875 percent) and 2035.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOKbs senior notes due 2015, 2022, 2028 and 2035 are senior unsecured obligations, ranking equally in right of payment with all of ONEOKbs existing and future unsecured senior indebtedness.

'

'ONEOK may redeem the senior notes due 2015, 2028 (6.875 percent) and 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the senior notes due 2028 (6.5 percent), in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest.B B ONEOK may redeem the remaining balance of its 4.25-percent senior notes due 2022 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three months before the maturity date.B B Prior to this date, ONEOK may redeem these senior notes on the same basis as its other senior notes due 2015, 2028 (6.875 percent) and 2035.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOKbs senior notes due 2015, 2022, 2028 and 2035 are senior unsecured obligations, ranking equally in right of payment with all of ONEOKbs existing and future unsecured senior indebtedness.

'

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'ONEOK may redeem the senior notes due 2015, 2028 (6.875 percent) and 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the senior notes due 2028 (6.5 percent), in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest.B B ONEOK may redeem the remaining balance of its 4.25-percent senior notes due 2022 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three months before the maturity date.B B Prior to this date, ONEOK may redeem these senior notes on the same basis as its other senior notes due 2015, 2028 (6.875 percent) and 2035.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOKbs senior notes due 2015, 2022, 2028 and 2035 are senior unsecured obligations, ranking equally in right of payment with all of ONEOKbs existing and future unsecured senior indebtedness.

'

'ONEOK may redeem the senior notes due 2015, 2028 (6.875 percent) and 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK may redeem the senior notes due 2028 (6.5 percent), in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest.B B ONEOK may redeem the remaining balance of its 4.25-percent senior notes due 2022 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting three months before the maturity date.B B Prior to this date, ONEOK may redeem these senior notes on the same basis as its other senior notes due 2015, 2028 (6.875 percent) and 2035.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOKbs senior notes due 2015, 2022, 2028 and 2035 are senior unsecured obligations, ranking equally in right of payment with all of ONEOKbs existing and future unsecured senior indebtedness.

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'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

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'

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'ONEOK Partners may redeem its senior notes due 2016 (6.15 percent), 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium.B B The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B B ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2016 (3.25 percent) and 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting one month and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these senior notes in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partnersb may redeem its senior notes due 2018, 2023, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partnersb may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.B ONEOK Partnersb senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK Partnersb existing and future unsecured senior indebtedness, and are structurally subordinate to all of the existing and future debt and other liabilities of any nonguarantor subsidiaries.B B ONEOK Partnersb senior notes are nonrecourse to ONEOK.

'

'

'

'

'

Debt instrument covenant description

'

'

'

'

'

'The indentures governing ONEOKbs senior notes due 2028 (6.5 percent and 6.875 percent) include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2015, 2022 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more.B B Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2015, 2022, 2028 and 2035 to declare those senior notes immediately due and payable in full.

'

'

'The indentures governing ONEOKbs senior notes due 2028 (6.5 percent and 6.875 percent) include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2015, 2022 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more.B B Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2015, 2022, 2028 and 2035 to declare those senior notes immediately due and payable in full.

'

'The indentures governing ONEOKbs senior notes due 2028 (6.5 percent and 6.875 percent) include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2015, 2022 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more.B B Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2015, 2022, 2028 and 2035 to declare those senior notes immediately due and payable in full.

'

'

'

'The indentures governing ONEOKbs senior notes due 2028 (6.5 percent and 6.875 percent) include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2015, 2022 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more.B B Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2015, 2022, 2028 and 2035 to declare those senior notes immediately due and payable in full.

'

'The indentures governing ONEOKbs senior notes due 2028 (6.5 percent and 6.875 percent) include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the senior notes due 2015, 2022 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more.B B Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding senior notes due 2015, 2022, 2028 and 2035 to declare those senior notes immediately due and payable in full.

'

'

'

'

'

'

'

'The Guardian Pipeline senior notes were issued under a master shelf agreement dated November 8, 2001, with certain financial institutions.B B Principal payments are due quarterly through 2022. These senior notes contain financial covenants that require the maintenance of certain ratios defined in the master shelf agreement based on Guardian Pipelinebs financial position and results of operations.B B Upon any breach of these covenants, all amounts outstanding under the master shelf agreement may become due and payable immediately.B B At December 31, 2013, Guardian Pipeline was in compliance with its financial covenants.

'

'

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'ONEOK Partners senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partnersb ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partnersb outstanding senior notes to declare those notes immediately due and payable in full.

'

'

'

'

'

2014

10,700,000

'

3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,700,000

'

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2015

410,700,000

'

403,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,700,000

'

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2016

1,110,700,000

'

3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,700,000

'

1,100,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2017

410,700,000

'

3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,700,000

'

400,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2018

435,700,000

'

3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,700,000

'

425,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Underwritten public offering

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,250,000,000

1,300,000,000

Net proceeds from public offering

'

'

'

'

'

'

'

'

'

694,300,000

'

'

'

'

'

'

'

'

1,190,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,240,000,000

1,290,000,000

Related Party Transaction, Amounts of Transaction

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,130,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Extinguishment of Debt, Amount

'

'

'

'

400,000,000

'

'

152,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Early Repayment of Senior Debt

'

'

'

'

429,000,000

'

'

150,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt

$7,754,975,000

$6,515,372,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

MasterShelfAgreementInitiationDate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'November 8, 2001

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

EQUITY_Details

EQUITY (Details) (USD $)

3 Months Ended

12 Months Ended

In Millions, except Per Share data, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Equity [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accelerated share repurchases price paid

'

'

'

'

'

$150

'

'

'

$300

'

'

'

'

$150

$300

Accelerated share repurchases (in shares)

'

'

'

'

'

3.4

'

'

'

8.6

'

'

'

'

3.4

8.6

Common stock authorized and unreserved common stock available for issuance. (in shares)

'

362.4

'

'

'

'

'

'

'

'

'

'

'

362.4

'

'

Dividends paid

'

'

'

'

'

'

'

'

'

'

'

'

'

304.7

262

227

Dividend paid (in dollars per share)

'

$0.38

$0.38

$0.36

$0.36

$0.33

$0.33

$0.31

$0.31

$0.28

$0.28

$0.26

$0.26

$1.48

$1.27

$1.08

Dividend declared (in dollars per share)

$0.40

'

'

'

'

'

'

'

'

'

'

'

'

$1.48

$1.27

$1.08

Accelerated Share Repurchases authorized amount

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$750

ACCUMULATED_OTHER_COMPREHENSIV2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	($43,168)	($55,030)	($55,367)
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	857	1,034	987
Other comprehensive income (loss) before reclassifications	8,842	16,709	'
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax	-177	47	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, Portion Attributable to Parent	37,144	-47,004	'
Other comprehensive income (loss) before reclassifications	45,809	-30,248	'
Other Comprehensive Income Loss, Reclassification Adjustment on Derivatives	3,020	-16,372	'
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax	0	0	'
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Net of Tax	45,982	35,943	'
Other Comprehensive Income (Loss), Reclassification Adjustment included in Net Income, Net of Tax	49,002	19,571	'
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	11,862	337	'
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent	-177	47	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax, Portion Attributable to Parent	83,126	-11,061	'
Income tax expense	1,905	-10,327	-53,714
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	-7,926	49,499	84,025
Balance of accumulated other comprehensive income (loss) [Abstract]	'	'	'
Pension and Postretirement Benefit Plan Obligations	-79,676	-162,802	-151,741
Accumulated Other Comprehensive Income (Loss)	-121,987	-216,798	-206,121
Other comprehensive income (loss) attributable to ONEOK [Abstract]	'	'	'
Unrealized Holding Gains (Losses) on Investment Securities	-177	47	-384
Pension and Postretirement Benefit Plan Obligations	-83,126	11,061	25,837
Accumulated Other Comprehensive Income (Loss)	94,811	-10,677	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Total before tax [Member]	'	'	'
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	9,831	'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Tax benefit [Member]	'	'	'
Income tax expense	-1,905	'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Commodity Contract [Member] | Sales [Member]	'	'	'
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion	-19,049	'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Commodity Contract [Member] | Cost of Sales [Member]	'	'	'
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	14,320	'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Interest Rate Contract [Member] | Interest Expense [Member]	'	'	'
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	14,560	'	'
Accumulated Defined Benefit Plans Adjustment [Member]	'	'	'
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Net of Tax	45,982	'	'
Defined Benefit Plan, Amortization of Net Gains (Losses)	78,887	'	'
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)	-5,522	'	'
Amortization of unrecognized net asset at adoption	284	'	'
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	1,338	'	'
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax	74,987	'	'
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Tax	-29,005	'	'
Cash Flow Hedging [Member]	'	'	'
Other comprehensive income (loss) before reclassifications	31,183	33,427	-11,158
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	9,831	-59,826	-137,739
Cash Flow Hedging [Member] | Commodity Contract [Member]	'	'	'
Other comprehensive income (loss) before reclassifications	-15,433	62,898	117,508
Cash Flow Hedging [Member] | Commodity Contract [Member] | Sales [Member]	'	'	'
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	-19,049	-140,862	-48,601
Cash Flow Hedging [Member] | Commodity Contract [Member] | Cost of Sales [Member]	'	'	'
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	14,320	73,881	-89,618
Cash Flow Hedging [Member] | Interest Rate Contract [Member]	'	'	'
Other comprehensive income (loss) before reclassifications	46,616	-29,471	-128,666
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Interest Expense [Member]	'	'	'
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	14,560	7,155	480
Cash Flow Hedging [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Net of tax [Member]	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	7,926	'	'
Cash Flow Hedging [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Net income attributable to noncontrolling interest [Member]	'	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	3,020	'	'
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Noncontrolling Interest	$4,906	'	'

EARNINGS_PER_SHARE_Details

EARNINGS PER SHARE (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basic EPS from continuing operations [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Income from continuing operations attributable to ONEOK available for common stock	'	'	'	'	'	'	'	'	$266,533	$346,340	$358,364
Shares	'	'	'	'	'	'	'	'	206,044	206,140	209,344
Per share amount	$0.44	$0.30	$0	$0.55	$0.55	$0.32	$0.29	$0.59	$1.29	$1.68	$1.71
Diluted EPS from continuing operations [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Effect of options and other dilutive securities	'	'	'	'	'	'	'	'	0	0	0
Effect of options and other dilutive securities, shares	'	'	'	'	'	'	'	'	3,651	4,570	5,154
Income from continuing operations attributable to ONEOK available for common stock and common stock equivalents	'	'	'	'	'	'	'	'	$266,533	$346,340	$358,364
Shares	'	'	'	'	'	'	'	'	209,695	210,710	214,498
Per share amount	$0.43	$0.30	$0	$0.54	$0.53	$0.31	$0.29	$0.58	$1.27	$1.64	$1.67

SHAREBASED_PAYMENTS_Details

SHARE-BASED PAYMENTS (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jan. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	'	0	0	0	'
Restricted Stock Units (RSUs) [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Outstanding awards vesting period (in years)	'	'3 years	'	'	'
Share-based compensation arrangement by share-based payment award, equity instruments other than options, reduction due to separation of ONE Gas	77,000	'	'	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, reduction due to separation of subsidiary	'	'	'	'	$2,400,000
Weighted Average Price [Abstract]	'	'	'	'	'
Nonvested beginning balance (in dollars per share)	$35.27	$27.21	'	'	'
Granted (in dollars per share)	'	$47.46	$36.65	$28.50	'
Released to participants (in dollars per share)	'	$19.06	'	'	'
Forfeited (in dollars per share)	'	$37.23	'	'	'
Nonvested ending balance (in dollars per share)	'	$35.27	$27.21	'	'
Fair value of shares granted	'	7,940,000	11,030,000	11,728,000	'
Unrecognized compensation cost related to our nonvested restricted stock unit awards	'	9,300,000	'	'	'
Period over which compensation cost related to nonvested restricted stock will be recognized (in years)	'	'1 year 8 months 4 days	'	'	'
Restricted stock units and performance stock units activity [Roll forward]	'	'	'	'	'
Nonvested beginning balance (in shares)	776,596	1,020,600	'	'	'
Granted (in shares)	'	167,301	'	'	'
Released to participants (in shares)	'	-384,883	'	'	'
Forfeited (in shares)	'	-26,422	'	'	'
Nonvested ending balance (in shares)	'	776,596	1,020,600	'	'
Stock Compensation Plan [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Number of shares of common stock reserved for issuance under the Plan. (in shares)	'	10,000,000	'	'	'
Shares reserved for issuance under the plan (in shares)	'	2,000,000	'	'	'
Forfeiture rate maximum (in hundredths)	'	3.00%	'	'	'
Share based compensation expense	'	28,600,000	22,600,000	40,700,000	'
Share based compensation tax benefit	'	17,600,000	14,200,000	25,700,000	'
Long Term Incentive Plan [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Number of shares of common stock reserved for issuance under the Plan. (in shares)	'	15,600,000	'	'	'
Shares reserved for issuance under the plan (in shares)	'	900,000	'	'	'
Performance Unit Awards [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Outstanding awards vesting period (in years)	'	'3 years	'	'	'
Share-based compensation arrangement by share-based payment award, equity instruments other than options, reduction due to separation of ONE Gas	151,000	'	'	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, reduction due to separation of subsidiary	'	'	'	'	5,600,000
Weighted Average Price [Abstract]	'	'	'	'	'
Nonvested beginning balance (in dollars per share)	$41.10	$32.74	'	'	'
Granted (in dollars per share)	'	$52.34	$42.39	$34.68	'
Released to participants (in dollars per share)	'	$24.05	'	'	'
Forfeited (in dollars per share)	'	$42.53	'	'	'
Nonvested ending balance (in dollars per share)	'	$41.10	$32.74	'	'
Fair value of shares granted	'	19,742,000	25,466,000	29,186,000	'
Unrecognized compensation cost related to our nonvested restricted stock unit awards	'	22,500,000	'	'	'
Period over which compensation cost related to nonvested restricted stock will be recognized (in years)	'	'1 year 8 months 8 days	'	'	'
Restricted stock units and performance stock units activity [Roll forward]	'	'	'	'	'
Nonvested beginning balance (in shares)	1,652,145	2,133,157	'	'	'
Granted (in shares)	'	377,200	'	'	'
Released to participants (in shares)	'	-801,354	'	'	'
Forfeited (in shares)	'	-56,858	'	'	'
Nonvested ending balance (in shares)	'	1,652,145	2,133,157	'	'
Volatility (in hundredths)	'	22.27%	27.00%	39.91%	'
Dividend Yield (in hundredths)	'	3.04%	2.86%	3.30%	'
Risk-free Interest Rate (in hundredths)	'	0.42%	0.38%	1.33%	'
Non-employees and Directors [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Number of shares of common stock reserved for issuance under the Plan. (in shares)	'	1,400,000	'	'	'
Shares reserved for issuance under the plan (in shares)	'	1,000,000	'	'	'
The maximum number of shares for which options or other awards may be granted to any employee during any year (in shares)	'	40,000	'	'	'
Employee Stock Purchase Plan [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Number of shares of common stock reserved for issuance under the Plan. (in shares)	'	11,600,000	'	'	'
Restricted stock units and performance stock units activity [Roll forward]	'	'	'	'	'
Maximum allowable percentage of annual base pay withheld to purchase our common stock (in hundredths)	'	10.00%	'	'	'
Maximum allowable percentage of annual base pay from all means to purchase our common stock (in hundredths)	'	10.00%	'	'	'
Purchase price percentage of the lower of its grant date or exercise date market price (in hundredths)	'	85.00%	'	'	'
Percentage of employees participating in the Employee Stock Purchase Plan (in hundredths)	'	52.00%	55.00%	56.00%	'
Compensation expense for the Employee Stock Purchase Plan	'	6,600,000	'	7,200,000	'
Shares sold under the Employee Stock Purchase Plan (in shares)	'	254,960	256,490	365,116	'
Share price of shares sold under the Employee Stock Purchase Plan (in dollars per share)	'	35.97	35.97	23.7	'
Employee Stock Award Program [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Number of shares of common stock reserved for issuance under the Plan. (in shares)	'	900,000	'	'	'
Shares reserved for issuance under the plan (in shares)	'	63,975	42,467	295,694	'
Share based compensation expense	'	$3,600,000	$1,900,000	$16,000,000	'
Description of the Plan	'	'Under our Employee Stock Award Program, we issued, for no monetary consideration, to all eligible employees one share of our common stock when the per-share closing price of our common stock on the NYSE was for the first time at or above $13 per share.	'	'	'

EMPLOYEE_BENEFIT_PLANS_Details

EMPLOYEE BENEFIT PLANS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Deferred tax liabilities	'	$2,172,987,000	$1,934,183,000	'
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	0	'	'	'
Description of plan amendment	'	'In December 2011, we announced to participants a change from a self-insured postretirement medical plan to a fully insured solution for plan participants who are medicare eligible.B B This announcement resulted in a $44.6 million reduction in our accumulated postretirement benefit obligation that was recognized in other comprehensive income and will be amortized to net periodic benefit cost over the expected remaining years of service for plan participants.	'	'
Amounts recognized in other comprehensive income (loss) [Abstract]	'	'	'	'
Total recognized in other comprehensive income (loss)	'	83,126,000	-11,061,000	-25,837,000
Amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense [Abstract]	'	'	'	'
Regulatory asset for regulated entities	'	-383,600,000	-585,000,000	'
Accumulated other comprehensive income (loss), net of tax	'	-79,676,000	-162,802,000	-151,741,000
Weighted average assumptions used to determine benefit obligations [Abstract]	'	'	'	'
Compensation increase rate - benefit obligation - minimum (in hundredths)	'	3.35%	3.45%	3.20%
Compensation increase rate, maximum (in hundredths)	'	3.40%	3.50%	3.80%
Weighted-average assumptions used to determine net periodic benfit costs [Abstract]	'	'	'	'
Expected long-term return on plan assets (in hundredths)	'	8.25%	8.25%	8.25%
Compensation increase rate, minimum (in hundredths)	'	3.45%	3.20%	3.30%
Compensation increase rate, maximum (in hundredths)	'	3.50%	3.80%	3.90%
Description of basis used to determine overall expected long-term rate of return on plan assets	'	'We determine our overall expected long-term rate of return on plan assets, based on our review of historical returns and economic growth models. We determine our discount rates annually.B B We estimate our discount rate based upon a comparison of the expected cash flows associated with our future payments under our pension and postretirement obligations to a hypothetical bond portfolio created using high-quality bonds that closely match expected cash flows.B Bond portfolios are developed by selecting a bond for each of the next 60 years based on the maturity dates of the bonds.B B Bonds selected to be included in the portfolios are only those rated by Moodybs as AA- or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.	'	'
Assumed health care cost trend rates [Abstract]	'	'	'	'
Year that the rate reaches the ultimate trend rate	'	'2022	'2022	'
One percentage point change in assumed healthcare cost trend rates [Abstract]	'	'	'	'
Effect of a one percentage point increase on total of service and interest cost	'	1,136,000	'	'
Effect of a one percentage point increase on postretirement benefit obligation	'	15,152,000	'	'
Effect of a one percentage point decrease on total of service and interest cost	'	-1,022,000	'	'
Effect of a one percentage point decrease on postretirement benefit obligation	'	-14,350,000	'	'
Target allocation for assets of the pension plan [Abstract]	'	'	'	'
U.S. large-cap equities	'	37.00%	'	'
Aggregate bonds	'	24.00%	'	'
Developed foreign large-cap equities	'	10.00%	'	'
Alternative investments	'	8.00%	'	'
Mid-cap equities	'	6.00%	'	'
Emerging markets equities	'	5.00%	'	'
Small-cap equities	'	4.00%	'	'
High yield bonds	'	3.00%	'	'
Developed foreign bonds	'	2.00%	'	'
Emerging market bonds	'	1.00%	'	'
Total	'	100.00%	'	'
Other Employee Benefit Plans - Thrift Plan [Abstract]	'	'	'	'
Contributions made to the Thrift Plan	'	17,000,000	16,400,000	15,900,000
Percent of employee contributions matched of eligible compensation (in hundredths)	'	100.00%	'	'
Maximum percentage of each participant's eligible compensation, subject to certain limits, matching (in hundredths)	'	6.00%	'	'
Profit-Sharing Plan [Abstract]	'	'	'	'
Contributions made to the Profit-Sharing Plan	'	5,100,000	6,600,000	6,700,000
Profit sharing contribution percentage	'	1.00%	'	'
Natural Gas Distribution [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Deferred tax liabilities	'	86,000,000	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	1,000,000,000	'	'
Change in Benefit Obligation [Roll Forward]	'	'	'	'
Benefit obligation, end of period	'	1,100,000,000	'	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	1,000,000,000	'	'
Amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense [Abstract]	'	'	'	'
Regulatory asset for regulated entities	'	-376,800,000	-577,100,000	'
Pension Benefits [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	1,112,749,000	995,264,000	902,235,000
Change in Benefit Obligation [Roll Forward]	'	'	'	'
Benefit obligation, beginning of period	1,221,449,000	1,313,560,000	1,215,932,000	'
Service cost	'	22,968,000	21,301,000	20,013,000
Interest cost	'	54,449,000	59,237,000	58,757,000
Plan participants' contributions	'	0	0	'
Actuarial (gain) loss	'	-110,552,000	105,732,000	'
Benefits paid	'	-58,976,000	-88,642,000	'
Plan amendment	'	0	0	'
Benefit obligation, end of period	'	1,221,449,000	1,313,560,000	1,215,932,000
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of plan assets, beginning of period	1,112,749,000	995,264,000	902,235,000	'
Actual return on plan assets	'	176,889,000	90,026,000	'
Employer contributions	'	0	91,881,000	'
Benefits paid	'	-59,404,000	-88,878,000	'
Fair value of assets, end of period	'	1,112,749,000	995,264,000	902,235,000
Balance at December 31	'	-108,700,000	-318,296,000	'
Current liabilities	'	-5,457,000	-4,695,000	'
Non-current liabilities	'	-103,243,000	-313,601,000	'
Balance at December 31	'	-108,700,000	-318,296,000	'
Accumulated benefit obligation for pension plans	'	1,159,000,000	1,240,300,000	'
Components of net periodic benefit cost [Abstract]	'	'	'	'
Service cost	'	22,968,000	21,301,000	20,013,000
Interest cost	'	54,449,000	59,237,000	58,757,000
Expected return on assets	'	-81,272,000	-82,756,000	-75,500,000
Amortization of unrecognized prior service cost	'	920,000	969,000	1,018,000
Defined Benefit Plan, Amortization of Transition Obligations (Assets)	0	'	'	'
Amortization of net loss	'	66,282,000	48,439,000	35,708,000
Settlements	'	1,338,000	1,401,000	0
Net periodic benefit cost	'	64,685,000	48,591,000	39,996,000
Amounts recognized in other comprehensive income (loss) [Abstract]	'	'	'	'
Regulatory asset gain (loss)	'	-110,437,000	67,472,000	114,625,000
Net gain (loss) arising during the period	'	201,251,000	-103,199,000	-182,987,000
Amortization of regulatory asset	'	-44,378,000	-32,527,000	-23,265,000
Prior service credit (cost)	193,000	920,000	969,000	1,018,000
Amortization of loss	'	67,620,000	49,839,000	35,708,000
Deferred income taxes	'	-44,473,000	6,748,000	21,236,000
Total recognized in other comprehensive income (loss)	'	70,503,000	-10,698,000	-33,665,000
Amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense [Abstract]	'	'	'	'
Transition obligation	'	0	0	'
Prior service credit (cost)	'	-1,102,000	-2,022,000	'
Accumulated gain (loss)	'	-415,375,000	-684,245,000	'
Accumulated other comprehensive income (loss) before regulatory assets	'	-416,477,000	-686,267,000	'
Regulatory asset for regulated entities	'	288,017,000	442,833,000	'
Accumulated other comprehensive income (loss) after regulatory assets	'	-128,460,000	-243,434,000	'
Deferred income taxes	'	49,689,000	94,161,000	'
Accumulated other comprehensive income (loss), net of tax	'	-78,771,000	-149,273,000	'
Amounts to be recognized in 2014 [Abstract]	'	'	'	'
Prior service credit (cost)	193,000	920,000	969,000	1,018,000
Net loss	15,021,000	'	'	'
Weighted average assumptions used to determine benefit obligations [Abstract]	'	'	'	'
Discount rate (in hundredths)	'	5.25%	4.25%	'
Weighted-average assumptions used to determine net periodic benfit costs [Abstract]	'	'	'	'
Discount rate (in hundredths)	'	4.25%	5.00%	5.50%
Level 3 fair value measurements [Roll Forward]	'	'	'	'
Balance at beginning of period	137,404,000	138,173,000	137,061,000	'
Actual return on plan assets held at the reporting date	'	-769,000	1,112,000	'
Balance at end of period	'	137,404,000	138,173,000	137,061,000
Benefits to be paid in: [Abstract]	'	'	'	'
2014	'	63,856,000	'	'
2015	'	64,588,000	'	'
2016	'	66,477,000	'	'
2017	'	68,626,000	'	'
2018	'	70,873,000	'	'
2019 through 2023	'	386,366,000	'	'
Pension Benefits [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	708,289,000	574,835,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	708,289,000	574,835,000	'
Pension Benefits [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	267,056,000	282,256,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	267,056,000	282,256,000	'
Pension Benefits [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	137,404,000	138,173,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	137,404,000	138,173,000	'
Pension Benefits [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	1,112,749,000	995,264,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	1,112,749,000	995,264,000	'
Pension Benefits [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	95,432,000	104,078,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	95,432,000	104,078,000	'
Pension Benefits [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Corporate Obligations [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	95,432,000	104,078,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	95,432,000	104,078,000	'
Pension Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member]	'	'	'	'
Level 3 fair value measurements [Roll Forward]	'	'	'	'
Balance at beginning of period	'	70,411,000	70,818,000	'
Actual return on plan assets held at the reporting date	'	-6,953,000	-407,000	'
Balance at end of period	'	63,458,000	70,411,000	'
Pension Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	63,458,000	70,411,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	63,458,000	70,411,000	'
Pension Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	63,458,000	70,411,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	63,458,000	70,411,000	'
Pension Benefits [Member] | Other Investments [Member]	'	'	'	'
Level 3 fair value measurements [Roll Forward]	'	'	'	'
Balance at beginning of period	'	67,762,000	66,243,000	'
Actual return on plan assets held at the reporting date	'	6,184,000	1,519,000	'
Balance at end of period	'	73,946,000	67,762,000	'
Pension Benefits [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	73,946,000	67,762,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	73,946,000	67,762,000	'
Pension Benefits [Member] | Other Investments [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	73,946,000	67,762,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	73,946,000	67,762,000	'
Pension Benefits [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	680,590,000	541,539,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	680,590,000	541,539,000	'
Pension Benefits [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	60,336,000	61,242,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	60,336,000	61,242,000	'
Pension Benefits [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Equity Securities [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	740,926,000	602,781,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	740,926,000	602,781,000	'
Pension Benefits [Member] | Government Obligations [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Government Obligations [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	111,288,000	116,936,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	111,288,000	116,936,000	'
Pension Benefits [Member] | Government Obligations [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Government Obligations [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	111,288,000	116,936,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	111,288,000	116,936,000	'
Pension Benefits [Member] | Cash and Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	27,699,000	33,296,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	27,699,000	33,296,000	'
Pension Benefits [Member] | Cash and Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Cash and Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Pension Benefits [Member] | Cash and Money Market Funds [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	27,699,000	33,296,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	27,699,000	33,296,000	'
Postretirement Benefits [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Minimum number of years of service for certain employees to be eligible to participate in welfare plans that provide postretirement medical and life insurance benefits	'	5	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	175,635,000	148,162,000	124,163,000
Change in Benefit Obligation [Roll Forward]	'	'	'	'
Benefit obligation, beginning of period	289,147,000	299,172,000	286,044,000	'
Service cost	'	4,612,000	4,960,000	4,987,000
Interest cost	'	11,713,000	13,893,000	15,632,000
Plan participants' contributions	'	4,293,000	5,851,000	'
Actuarial (gain) loss	'	-29,460,000	9,935,000	'
Benefits paid	'	-18,411,000	-21,380,000	'
Plan amendment	'	17,228,000	-131,000	'
Benefit obligation, end of period	'	289,147,000	299,172,000	286,044,000
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of plan assets, beginning of period	175,635,000	148,162,000	124,163,000	'
Actual return on plan assets	'	27,483,000	14,273,000	'
Employer contributions	'	866,000	10,728,000	'
Benefits paid	'	-876,000	-1,002,000	'
Fair value of assets, end of period	'	175,635,000	148,162,000	124,163,000
Balance at December 31	'	-113,512,000	-151,010,000	'
Current liabilities	'	0	0	'
Non-current liabilities	'	-113,512,000	-151,010,000	'
Balance at December 31	'	-113,512,000	-151,010,000	'
Defined Benefit Plan, Contributions by Employer Including Claims Paid Directly	'	11,800,000	'	'
Components of net periodic benefit cost [Abstract]	'	'	'	'
Service cost	'	4,612,000	4,960,000	4,987,000
Interest cost	'	11,713,000	13,893,000	15,632,000
Expected return on assets	'	-12,259,000	-10,687,000	-10,272,000
Amortization of unrecognized prior service cost	'	-6,442,000	-8,252,000	-2,518,000
Defined Benefit Plan, Amortization of Transition Obligations (Assets)	'	284,000	2,874,000	3,189,000
Amortization of net loss	'	12,605,000	13,184,000	8,123,000
Net periodic benefit cost	'	10,513,000	15,972,000	19,141,000
Amounts recognized in other comprehensive income (loss) [Abstract]	'	'	'	'
Regulatory asset gain (loss)	'	-7,674,000	4,376,000	7,389,000
Net gain (loss) arising during the period	'	44,685,000	-6,348,000	-40,765,000
Amortization of regulatory asset	'	-5,643,000	-6,557,000	-7,214,000
Amortization of transition obligation	0	284,000	2,874,000	3,189,000
Prior service credit (cost)	-1,662,000	-6,442,000	-8,252,000	-2,518,000
Amortization of loss	'	12,605,000	13,184,000	8,123,000
Defined Benefit Plan, Plan Amendments	'	-17,228,000	131,000	44,562,000
Deferred income taxes	'	-7,964,000	229,000	-4,938,000
Total recognized in other comprehensive income (loss)	'	12,623,000	-363,000	7,828,000
Amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense [Abstract]	'	'	'	'
Transition obligation	'	0	-283,000	'
Prior service credit (cost)	'	14,631,000	38,301,000	'
Accumulated gain (loss)	'	-59,362,000	-116,652,000	'
Accumulated other comprehensive income (loss) before regulatory assets	'	-44,731,000	-78,634,000	'
Regulatory asset for regulated entities	'	43,254,000	56,571,000	'
Accumulated other comprehensive income (loss) after regulatory assets	'	-1,477,000	-22,063,000	'
Deferred income taxes	'	572,000	8,534,000	'
Accumulated other comprehensive income (loss), net of tax	'	-905,000	-13,529,000	'
Amounts to be recognized in 2014 [Abstract]	'	'	'	'
Transition obligation	0	284,000	2,874,000	3,189,000
Prior service credit (cost)	-1,662,000	-6,442,000	-8,252,000	-2,518,000
Net loss	833,000	'	'	'
Weighted average assumptions used to determine benefit obligations [Abstract]	'	'	'	'
Discount rate (in hundredths)	'	5.00%	4.00%	'
Weighted-average assumptions used to determine net periodic benfit costs [Abstract]	'	'	'	'
Discount rate (in hundredths)	'	4.00%	5.00%	5.50%
Benefits to be paid in: [Abstract]	'	'	'	'
2014	'	16,251,000	'	'
2015	'	17,135,000	'	'
2016	'	18,142,000	'	'
2017	'	19,095,000	'	'
2018	'	19,875,000	'	'
2019 through 2023	'	106,346,000	'	'
Assumed health care cost trend rates [Abstract]	'	'	'	'
Health care cost-trend rate assumed for next year - minimum (in hundredths)	'	4.00%	4.00%	'
Health care cost-trend rate assumed for next year - maximum (in hundredths)	'	8.25%	9.00%	'
Rate to which the cost-trend rate is assumed to decline (the ultimate trend rate) - minimum (in hundredths)	'	4.00%	4.00%	'
Rate to which the cost-trend rate is assumed to decline (the ultimate trend rate) - maximum (in hundredths)	'	5.00%	5.00%	'
Postretirement Benefits [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	68,939,000	57,381,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	68,939,000	57,381,000	'
Postretirement Benefits [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	106,587,000	90,625,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	106,587,000	90,625,000	'
Postretirement Benefits [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	109,000	156,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	109,000	156,000	'
Postretirement Benefits [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	175,635,000	148,162,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	175,635,000	148,162,000	'
Postretirement Benefits [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	17,207,000	17,522,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	17,207,000	17,522,000	'
Postretirement Benefits [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	142,000	238,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	142,000	238,000	'
Postretirement Benefits [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Corporate Obligations [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	17,349,000	17,760,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	17,349,000	17,760,000	'
Postretirement Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	106,189,000	89,979,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	106,189,000	89,979,000	'
Postretirement Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Insurance Contracts and Group Annuity Contracts [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	106,189,000	89,979,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	106,189,000	89,979,000	'
Postretirement Benefits [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	109,000	156,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	109,000	156,000	'
Postretirement Benefits [Member] | Other Investments [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	109,000	156,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	109,000	156,000	'
Postretirement Benefits [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	37,796,000	21,548,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	37,796,000	21,548,000	'
Postretirement Benefits [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	90,000	140,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	90,000	140,000	'
Postretirement Benefits [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Equity Securities [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	37,886,000	21,688,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	37,886,000	21,688,000	'
Postretirement Benefits [Member] | Government Obligations [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Government Obligations [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	166,000	268,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	166,000	268,000	'
Postretirement Benefits [Member] | Government Obligations [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Government Obligations [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	166,000	268,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	166,000	268,000	'
Postretirement Benefits [Member] | Cash and Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	13,936,000	18,311,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	13,936,000	18,311,000	'
Postretirement Benefits [Member] | Cash and Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Cash and Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	0	0	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	0	0	'
Postretirement Benefits [Member] | Cash and Money Market Funds [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Defined Benefit Plan, Fair Value of Plan Assets	'	13,936,000	18,311,000	'
Change in Plan Assets [Roll Forward]	'	'	'	'
Fair value of assets, end of period	'	13,936,000	18,311,000	'
Pension and postretirement unrecognized losses [Member] | Natural Gas Distribution [Member]	'	'	'	'
Amounts in accumulated other comprehensive income (loss) that had not yet been recognized as components of net periodic benefit expense [Abstract]	'	'	'	'
Regulatory asset for regulated entities	'	($331,100,000)	'	'

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	1 Months Ended	12 Months Ended
	Jan. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax [Line Items]	'	'	'	'
Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Operating Activities	'	$35,900,000	$11,000,000	'
Current income taxes	'	'	'	'
Federal	'	7,313,000	-16,083,000	-32,291,000
State	'	4,554,000	1,798,000	1,707,000
Total current income taxes from continuing operations	'	11,867,000	-14,285,000	-30,584,000
Deferred income taxes	'	'	'	'
Federal	'	137,654,000	213,127,000	228,257,000
State	'	13,861,000	16,353,000	28,375,000
Total deferred income taxes from continuing operations	'	151,515,000	229,480,000	256,632,000
Total provision for income taxes from continuing operations	'	163,382,000	215,195,000	226,048,000
Discontinued operations	468,000	0	8,749,000	1,255,000
Total provision for income taxes	'	163,382,000	223,944,000	227,303,000
Reclassification from current income taxes	'	'	'	37,700,000
Reconciliation for income tax provision [Abstract]	'	'	'	'
Income from continuing operations before income taxes	'	740,343,000	944,446,000	983,562,000
Less: Net income attributable to noncontrolling interests	'	310,428,000	382,911,000	399,150,000
Income from continuing operations attributable to ONEOK before income taxes	'	429,915,000	561,535,000	584,412,000
Federal statutory income tax rate	'	35.00%	35.00%	35.00%
Provision for federal income taxes	'	150,470,000	196,537,000	204,543,000
State income taxes, net of federal tax benefit	'	11,970,000	11,799,000	20,334,000
Other, net	'	942,000	6,859,000	1,171,000
Total provision for income taxes from continuing operations	'	163,382,000	215,195,000	226,048,000
Deferred tax assets	'	'	'	'
Employee benefits and other accrued liabilities	'	78,793,000	128,418,000	'
Federal net operating loss	'	12,484,000	0	'
State net operating loss and benefits	'	38,322,000	31,990,000	'
Energy Services capacity release	'	46,726,000	0	'
Other comprehensive income	'	78,369,000	140,802,000	'
Other	'	20,872,000	1,446,000	'
Total deferred tax assets	'	275,566,000	302,656,000	'
Deferred tax liabilities	'	'	'	'
Excess of tax over book depreciation and depletion	'	822,706,000	760,211,000	'
Investment in partnerships	'	1,217,605,000	969,347,000	'
Regulatory assets	'	132,676,000	204,625,000	'
Total deferred tax liabilities	'	2,172,987,000	1,934,183,000	'
Deferred Tax Liabilities, Net	'	1,897,421,000	1,631,527,000	'
Income taxes receivable	'	$15,600,000	$30,800,000	'

UNCONSOLIDATED_AFFILIATES_Deta

UNCONSOLIDATED AFFILIATES (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Equity Method Investments [Line Items]	'	'	'
Investments in unconsolidated affiliates	$1,229,838,000	$1,221,405,000	$1,223,398,000
Equity earnings from investments	110,517,000	123,024,000	127,246,000
Equity method goodwill	224,300,000	'	'
Payments to Acquire Other Investments	35,308,000	30,768,000	64,491,000
Balance Sheet [Abstract]	'	'	'
Current assets	155,310,000	175,930,000	'
Property, plant and equipment, net	2,557,571,000	2,593,122,000	'
Other noncurrent assets	34,478,000	35,005,000	'
Current liabilities	98,967,000	145,147,000	'
Long-term debt	442,103,000	472,630,000	'
Other noncurrent liabilities	58,221,000	42,451,000	'
Accumulated other comprehensive income (loss)	-2,291,000	-2,503,000	'
Owners' equity	2,150,359,000	2,146,332,000	'
Income Statement [Abstract]	'	'	'
Operating revenues	528,665,000	573,197,000	496,158,000
Cost and expenses	256,292,000	269,858,000	221,261,000
Net income	248,998,000	279,766,000	249,559,000
Distributions paid to us	137,498,000	155,741,000	156,385,000
Overland Pass Pipeline Company [Member]	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Investments in unconsolidated affiliates	466,671,000	468,710,000	'
Equity earnings from investments	20,461,000	20,043,000	19,535,000
Net ownership percentage	50.00%	'	'
Northern Border Pipeline [Member]	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Investments in unconsolidated affiliates	404,803,000	393,317,000	'
Equity earnings from investments	65,046,000	72,705,000	76,365,000
Net ownership percentage	50.00%	'	'
Percentage decrease in long-term transportation rates	11.00%	'	'
Payments to Acquire Other Investments	30,800,000	'	'
Fort Union Gas Gathering LLC [Member]	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Investments in unconsolidated affiliates	125,220,000	120,782,000	'
Equity earnings from investments	15,826,000	17,218,000	15,280,000
Net ownership percentage	37.00%	'	'
Bighorn Gas Gathering LLC [Member]	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Investments in unconsolidated affiliates	87,837,000	90,428,000	'
Equity earnings from investments	1,952,000	3,820,000	5,990,000
Equity method goodwill	53,400,000	'	'
Net ownership percentage	49.00%	'	'
Other Unconsolidated Affiliate [Member]	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Investments in unconsolidated affiliates	145,307,000	148,168,000	'
Equity earnings from investments	7,232,000	9,238,000	10,076,000
Unconsolidated Affiliates [Member]	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Related Party Transaction, Expenses from Transactions with Related Party	$53,800,000	$36,500,000	$33,700,000

ONEOK_PARTNERS_Details

ONEOK PARTNERS (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Rate
Related Party Transaction [Line Items]	'	'	'
Business Acquisition, Cost of Acquired Entity, Purchase Price	$304,889,000	'	'
Business Acquisition, Purchase Price Allocation, Goodwill Amount	92,000,000	'	'
Previously unowned share in Maysville natural gas processing facility	30.00%	'	'
Payment to acquire unowned interest in Maysville natural gas processing facilities	90,000,000	'	'
Asset acquisition, effective date of acquisition	1-Dec-13	'	'
Current ownership share in Maysville natural gas processing facility	100.00%	'	'
Aggregate amount of common units available for issuance and sale under the Equity Distribution Agreement.	300,000,000	'	'
Partners capital account units sold under equity distribution agreement	681,000	'	'
Partners' Capital Account, Units, Sold in Public Offering	11,500,000	8,000,000	'
Public offering price of common units	$49.61	$59.27	'
Proceeds from Sale of Interest in Partnership Unit	'	460,000,000	'
Partners' Capital Account, Units, Sold in Private Placement	'	8,000,000	'
Proceeds from Issuance of Private Placement	'	460,000,000	'
Partners' Capital Account, Contributions	'	19,000,000	'
Repayment on line of credit facility	'	295,000,000	'
Ownership interest	41.20%	43.40%	42.80%
Common units	19,800,000	'	'
Class B units	73,000,000	'	'
Payment to acquire OBPI	'	'	94,200,000
Partnership agreement	'Cash Distributions - We receive distributions from ONEOK Partners on our common and Class B units and our 2 percent general partner interest, which includes our incentive distribution rights.B B Under ONEOK Partnersb partnership agreement, as amended, distributions are made to the partners with respect to each calendar quarter in an amount equal to 100 percent of available cash as defined in the ONEOK Partners partnership agreement (Partnership Agreement), as amended.B B Available cash generally will be distributed 98 percent to limited partners and 2 percent to the general partner.B B The general partnerbs percentage interest in quarterly distributions is increased after certain specified target levels are met during the quarter.B B In July 2011, the Partnership Agreement was amended to adjust the formula for distributing available cash among the general partner and limited partners to reflect the two-for-one unit split of ONEOK Partnersb common units.B B Under the incentive distribution provisions, as set forth in ONEOK Partnersb partnership agreement, as amended, the general partner receives: 15 percent of amounts distributed in excess of $0.3025 per unit; 25 percent of amounts distributed in excess of $0.3575 per unit; and 50 percent of amounts distributed in excess of $0.4675 per unit.	'	'
Expenses [Abstract]	'	'	'
Noncontrolling Interest, Increase from Equity Issuance or Sale of Parent Equity Interest	533,824,000	459,587,000	'
ONEOK, Inc. [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Revenues	'	352,099,000	403,603,000
Expenses [Abstract]	'	'	'
Cost of sales and fuel	'	33,094,000	48,163,000
Administrative and general expenses	'	246,050,000	251,239,000
Total expenses	303,411,000	279,144,000	299,402,000
General Partner [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Ownership interest	2.00%	2.00%	'
Limited Partner [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Ownership interest	39.20%	'	'
Dividend Paid [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Total distributions	909,713,000	760,912,000	609,446,000
Distribution (in dollars per unit)	$2.87	$2.59	$2.33
Dividend Paid [Member] | General Partner [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
General partner distributions	18,193,000	15,217,000	12,189,000
Incentive distributions	251,664,000	186,130,000	123,386,000
Distributions to general partner	269,857,000	201,347,000	135,575,000
Dividend Paid [Member] | Limited Partner [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Limited partner distributions to ONEOK	266,302,000	235,442,000	197,132,000
Limited partner distributions to noncontrolling interest	373,554,000	324,123,000	276,739,000
Dividend Declared [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Total distributions	931,236,000	817,754,000	625,751,000
Distribution (in dollars per unit)	$2.89	$2.69	$2.37
Dividend Declared [Member] | General Partner [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
General partner distributions	18,625,000	16,355,000	12,515,000
Incentive distributions	259,466,000	210,095,000	131,212,000
Distributions to general partner	278,091,000	226,450,000	143,727,000
Dividend Declared [Member] | Limited Partner [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Limited partner distributions to ONEOK	268,157,000	249,600,000	200,524,000
Limited partner distributions to noncontrolling interest	384,988,000	341,704,000	281,500,000
Notes Payables due 2012 [Member] | Partnership Interest [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	'	5.90%	'
Debt Instrument, Maturity Date	'	1-Apr-12	'
Issued under public offering [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Proceeds from Sale of Interest in Partnership Unit	553,300,000	'	'
Partners' Capital Account, Contributions	11,600,000	'	'
Additional Paid-in Capital [Member]	'	'	'
Expenses [Abstract]	'	'	'
Noncontrolling Interest, Increase from Equity Issuance or Sale of Parent Equity Interest	87,295,000	-51,100,000	'
issued under equity distribution agreement [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Proceeds from Sale of Interest in Partnership Unit	$36,100,000	'	'
Minimum [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Useful Life	'20 years	'	'
Maximum [Member]	'	'	'
Related Party Transaction [Line Items]	'	'	'
Useful Life	'30 years	'	'

ONEOK_PARTNERS_Schedule_of_pur

ONEOK PARTNERS Schedule of purchase price allocation (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Business Combination, Separately Recognized Transactions [Line Items]	'
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	$103,000
Business Acquisition, Purchase Price Allocation, Assets Acquired	212,889
Business Acquisition, Purchase Price Allocation, Goodwill Amount	92,000
Business Acquisition, Cost of Acquired Entity, Purchase Price	304,889
Gathering pipelines and related equipment [Member]	'
Business Combination, Separately Recognized Transactions [Line Items]	'
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment	59,174
Processing and fractionation and related equipment [Member]	'
Business Combination, Separately Recognized Transactions [Line Items]	'
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment	50,595
General plant and other [Member]	'
Business Combination, Separately Recognized Transactions [Line Items]	'
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment	$120

COMMITMENTS_AND_CONTINGENCIES_1

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified	Y
Commitments and Contingencies Disclosure [Abstract]	'
Number of former manufactured gas sites in Kansas where we own or retain legal responsibility for environmental conditions	12
Number of sites where soil remediation has begun	11
Number of sites where regulatory closure has been achieved	3
Number of sites soil remediation is completed or near completion	8
Number of years of consideration for EPA lowering threshold levels for greenhouse gas emissions	5
Minimum percentage yield of high consequence pipeline areas	30.00%
Operating Leases, Future Minimum Payments Due [Abstract]	'
2014	$2
2015	0.5
2016	0.3
2017	0.2
2018	0.2
Thereafter	0.7
Firm Transportation and Storage Contracts, Future Minimum Payments Due [Abstract]	'
2014	18.4
2015	16.3
2016	14.4
2017	12.8
2018	11.9
Thereafter	30.2
ONE Gas [Member]	'
Operating Leased Assets [Line Items]	'
Unrecorded Unconditional Purchase Obligation	900
ONEOK [Member]	'
Operating Leased Assets [Line Items]	'
Unrecorded Unconditional Purchase Obligation	11.2
Partnership Interest [Member]	'
Operating Leases, Future Minimum Payments Due [Abstract]	'
Total	3.9
Firm Transportation and Storage Contracts, Future Minimum Payments Due [Abstract]	'
Total	104
Total Commitments and Contingencies [Abstract]	'
2014	20.4
2015	16.8
2016	14.7
2017	13
2018	12.1
Thereafter	30.9
Total Commitments and Contingencies	107.9
Parent Company [Member]	'
Operating Leases, Future Minimum Payments Due [Abstract]	'
2014	3.4
2015	2.9
2016	2.5
2017	2.1
2018	1.9
Thereafter	3.3
Total	$16.10

SEGMENTS_Details

SEGMENTS (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting, Disclosure of Major Customers	'	'	'	'	'	'	'	'	'we had no single external customer from which we received 10 percent or more of our consolidated gross revenues.	'we had no single external customer from which we received 10 percent or more of our consolidated gross revenues.	'we had no single external customer from which we received 10 percent or more of our consolidated gross revenues.
Ownership interest	'	'	'	'	'	'	'	'	41.20%	43.40%	42.80%
Sales to unaffiliated customers	'	'	'	'	'	'	'	'	$14,602,717	$12,632,559	$14,805,794
Intersegment revenues	'	'	'	'	'	'	'	'	0	0	0
Total revenues	4,140,111	3,571,925	3,349,236	3,541,445	3,659,924	3,028,775	2,529,260	3,414,600	14,602,717	12,632,559	14,805,794
Net margin	651,654	561,188	453,389	623,452	604,320	553,972	548,962	643,587	2,289,683	2,350,841	2,380,359
Operating costs	'	'	'	'	'	'	'	'	990,453	908,978	908,323
Depreciation and amortization	'	'	'	'	'	'	'	'	384,377	335,844	312,160
Goodwill, Impairment Loss	'	'	'	'	'	'	'	'	0	10,255	0
Gain (loss) on sale of assets	'	'	'	'	'	'	'	'	11,881	6,736	-963
Operating income	'	'	'	'	'	'	'	'	926,734	1,102,500	1,158,913
Equity earnings from investments	'	'	'	'	'	'	'	'	110,517	123,024	127,246
Investments in unconsolidated affiliates	1,229,838	'	'	'	1,221,405	'	'	'	1,229,838	1,221,405	1,223,398
Total assets	17,707,558	'	'	'	15,855,275	'	'	'	17,707,558	15,855,275	13,696,635
Noncontrolling interests in consolidated subsidiaries	2,507,329	'	'	'	2,102,841	'	'	'	2,507,329	2,102,841	1,561,159
Capital expenditures	'	'	'	'	'	'	'	'	2,256,585	1,866,153	1,336,067
Natural Gas Distribution [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Sales to unaffiliated customers	'	'	'	'	'	'	'	'	1,689,945	1,379,366	1,609,628
Intersegment revenues	'	'	'	'	'	'	'	'	7	-2,717	11,706
Total revenues	'	'	'	'	'	'	'	'	1,689,952	1,376,649	1,621,334
Net margin	'	'	'	'	'	'	'	'	813,008	756,389	751,835
Operating costs	'	'	'	'	'	'	'	'	444,866	410,572	422,073
Depreciation and amortization	'	'	'	'	'	'	'	'	144,758	130,150	132,212
Goodwill, Impairment Loss	'	'	'	'	'	'	'	'	'	0	'
Gain (loss) on sale of assets	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	223,384	215,667	197,550
Equity earnings from investments	'	'	'	'	'	'	'	'	0	0	0
Investments in unconsolidated affiliates	0	'	'	'	0	'	'	'	0	0	0
Total assets	3,857,722	'	'	'	3,535,489	'	'	'	3,857,722	3,535,489	3,392,475
Noncontrolling interests in consolidated subsidiaries	0	'	'	'	0	'	'	'	0	0	0
Capital expenditures	'	'	'	'	'	'	'	'	292,080	280,294	242,590
Energy Services [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Sales to unaffiliated customers	'	'	'	'	'	'	'	'	1,381,636	1,421,171	2,274,799
Intersegment revenues	'	'	'	'	'	'	'	'	195,926	105,402	502,418
Total revenues	'	'	'	'	'	'	'	'	1,577,562	1,526,573	2,777,217
Net margin	'	'	'	'	'	'	'	'	-172,985	-49,344	48,740
Operating costs	'	'	'	'	'	'	'	'	13,133	17,950	24,527
Depreciation and amortization	'	'	'	'	'	'	'	'	277	361	445
Goodwill, Impairment Loss	'	'	'	'	'	'	'	'	'	10,255	'
Gain (loss) on sale of assets	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	-186,395	-77,910	23,768
Equity earnings from investments	'	'	'	'	'	'	'	'	0	0	0
Investments in unconsolidated affiliates	0	'	'	'	0	'	'	'	0	0	0
Total assets	347,470	'	'	'	493,006	'	'	'	347,470	493,006	562,728
Noncontrolling interests in consolidated subsidiaries	0	'	'	'	0	'	'	'	0	0	0
Capital expenditures	'	'	'	'	'	'	'	'	0	0	41
Corporate Elimination [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Sales to unaffiliated customers	'	'	'	'	'	'	'	'	2,606	1,970	2,363
Intersegment revenues	'	'	'	'	'	'	'	'	-536,676	-454,784	-917,727
Total revenues	'	'	'	'	'	'	'	'	-534,070	-452,814	-915,364
Net margin	'	'	'	'	'	'	'	'	2,600	1,964	2,404
Operating costs	'	'	'	'	'	'	'	'	10,941	-2,084	2,359
Depreciation and amortization	'	'	'	'	'	'	'	'	2,599	2,232	1,954
Goodwill, Impairment Loss	'	'	'	'	'	'	'	'	'	0	'
Gain (loss) on sale of assets	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	-10,940	1,816	-1,909
Equity earnings from investments	'	'	'	'	'	'	'	'	0	0	0
Investments in unconsolidated affiliates	0	'	'	'	0	'	'	'	0	0	0
Total assets	639,758	'	'	'	867,550	'	'	'	639,758	867,550	794,756
Noncontrolling interests in consolidated subsidiaries	2,502,793	'	'	'	2,098,074	'	'	'	2,502,793	2,098,074	1,556,047
Capital expenditures	'	'	'	'	'	'	'	'	25,179	25,346	30,053
Oneok Partners [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Sales to unaffiliated customers	'	'	'	'	'	'	'	'	11,528,530	9,830,052	10,919,004
Intersegment revenues	'	'	'	'	'	'	'	'	340,743	352,099	403,603
Total revenues	'	'	'	'	'	'	'	'	11,869,273	10,182,151	11,322,607
Net margin	'	'	'	'	'	'	'	'	1,647,060	1,641,832	1,577,380
Operating costs	'	'	'	'	'	'	'	'	521,513	482,540	459,364
Depreciation and amortization	'	'	'	'	'	'	'	'	236,743	203,101	177,549
Goodwill, Impairment Loss	'	'	'	'	'	'	'	'	'	0	'
Gain (loss) on sale of assets	'	'	'	'	'	'	'	'	11,881	6,736	-963
Operating income	'	'	'	'	'	'	'	'	900,685	962,927	939,504
Equity earnings from investments	'	'	'	'	'	'	'	'	110,517	123,024	127,246
Investments in unconsolidated affiliates	1,229,838	'	'	'	1,221,405	'	'	'	1,229,838	1,221,405	1,223,398
Total assets	12,862,608	'	'	'	10,959,230	'	'	'	12,862,608	10,959,230	8,946,676
Noncontrolling interests in consolidated subsidiaries	4,536	'	'	'	4,767	'	'	'	4,536	4,767	5,112
Capital expenditures	'	'	'	'	'	'	'	'	1,939,326	1,560,513	1,063,383
Oneok Partners [Member] | Regulated Segment [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Total revenues	'	'	'	'	'	'	'	'	781,700	722,100	658,500
Net margin	'	'	'	'	'	'	'	'	545,000	618,000	469,000
Operating income	'	'	'	'	'	'	'	'	$281,000	$375,600	$232,800

QUARTERLY_FINANCIAL_DATA_UNAUD2

QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Total revenues	$4,140,111	$3,571,925	$3,349,236	$3,541,445	$3,659,924	$3,028,775	$2,529,260	$3,414,600	$14,602,717	$12,632,559	$14,805,794
Net margin	651,654	561,188	453,389	623,452	604,320	553,972	548,962	643,587	2,289,683	2,350,841	2,380,359
Income from continuing operations	184,063	147,698	79,495	165,705	195,875	164,988	148,938	219,450	576,961	729,251	757,514
Income from discontinued operations and gain on sale, net of tax	'	'	'	'	0	0	267	14,012	0	762	2,230
Net income	184,063	147,698	79,495	165,705	195,875	164,988	149,205	233,462	576,961	743,530	759,744
Net income attributable to ONEOK	$90,737	$62,356	$919	$112,521	$111,542	$65,219	$60,993	$122,865	$266,533	$360,619	$360,594
Earnings per share total	'	'	'	'	'	'	'	'	'	'	'
Basic (in dollars per share)	$0.44	$0.30	$0	$0.55	$0.55	$0.32	$0.29	$0.59	$1.29	$1.68	$1.71
Diluted (in dollars per share)	$0.43	$0.30	$0	$0.54	$0.53	$0.31	$0.29	$0.58	$1.27	$1.64	$1.67

SUBSEQUENT_EVENTS_Details

SUBSEQUENT EVENTS (Details) (USD $)

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Jan. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2014

ONE Gas [Member]

ONE Gas [Member]

ONE Gas [Member]

ONE Gas [Member]

ONE Gas [Member]

Parent Company [Member]

Parent Company [Member]

Parent Company [Member]

Parent Company [Member]

Parent Company [Member]

Parent Company [Member]

Parent Company [Member]

Parent Company [Member]

ONEOK [Member]

2.07% notes due February 1, 2019

3.61% notes due February 1, 2024

4.658% notes due February 1, 2044

Note Payable from Public Offering Due 2022 [Member]

Note Payable from Public Offering Due 2022 [Member]

Note Payable from Public Offering Due 2022 [Member]

Notes Payables due 2015 [Member]

Notes Payables due 2015 [Member]

Notes Payables due 2015 [Member]

Subsequent Event [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Extinguishment of Debt, Amount

'

'

'

'

'

'

'

'

'

$152,500,000

'

'

$400,000,000

'

'

'

Long-term Debt, Gross

7,756,180,000

6,514,047,000

'

1,200,000,000

300,000,000

300,000,000

600,000,000

1,688,972,000

1,689,190,000

'

700,000,000

700,000,000

'

400,000,000

400,000,000

'

Related Party Transaction, Amounts of Transaction

'

'

1,130,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Interest Rate, Stated Percentage

'

'

'

'

2.07%

3.61%

4.66%

'

'

'

4.25%

'

'

5.20%

'

'

Early Repayment of Senior Debt

'

'

'

'

'

'

'

'

'

150,000,000

'

'

429,000,000

'

'

'

Repayments of Commercial Paper

'

'

'

'

'

'

'

'

'

'

'

'

'

'

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$600,500,000