ONEOK Partners (OKS) 10-Q 5 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Oct. 28, 2014	Oct. 28, 2014
		Common Units [Member]	Class B Units [Member]
Document Information [Line Items]	'	'	'
Entity Registrant Name	'ONEOK Partners LP	'	'
Entity Central Index Key	'0000909281	'	'
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 Common Stock, Shares Outstanding	'	177,354,481	72,988,252
Document Fiscal Year Focus	'2014	'	'
Document Fiscal Period Focus	'Q3	'	'
Document Type	'10-Q	'	'
Amendment Flag	'false	'	'
Document Period End Date	30-Sep-14	'	'

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenues [Abstract]	'	'	'	'
Commodity sales	$2,754,495	$2,807,329	$8,276,333	$7,453,534
Services	364,874	327,404	1,071,074	966,825
Total revenues	3,119,369	3,134,733	9,347,407	8,420,359
Cost of sales and fuel	2,583,204	2,711,159	7,807,275	7,214,233
Net margin	536,165	423,574	1,540,132	1,206,126
Operating expenses	'	'	'	'
Operations and maintenance	152,533	108,978	425,715	338,353
Depreciation and amortization	73,901	61,182	212,083	174,086
General taxes	18,252	13,384	55,898	46,249
Total operating expenses	244,686	183,544	693,696	558,688
Gain (loss) on sale of assets	1,534	22	1,533	342
Operating income	293,013	240,052	847,969	647,780
Equity earnings (loss) from investments (Note J)	-52,347	27,468	6,747	79,744
Allowance for equity funds used during construction	1,723	6,429	13,947	21,172
Other income	79	3,753	3,003	8,229
Other expense	-2,496	-589	-3,056	-2,447
Interest expense (net of capitalized interest of $14,303, $14,320, $41,446 and $38,284, respectively)	-70,060	-57,722	-211,344	-171,118
Income before income taxes	169,912	219,391	657,266	583,360
Income taxes	-2,592	-2,991	-9,967	-7,821
Net income	167,320	216,400	647,299	575,539
Less: Net income attributable to noncontrolling interests	73	90	226	263
Net income attributable to ONEOK Partners, L.P.	167,247	216,310	647,073	575,276
Limited partners' interest in net income:	'	'	'	'
Net income attributable to ONEOK Partners, L.P.	167,247	216,310	647,073	575,276
General partner's interest in net income	-87,796	-71,344	-249,697	-202,732
Limited partners' interest in net income	$79,451	$144,966	$397,376	$372,544
Limited partners' net income per unit, basic and diluted (Note I)	$0.32	$0.64	$1.65	$1.68
Number of units used in computation (thousands)	249,091	226,991	240,604	222,322

CONSOLIDATED_STATEMENT_OF_INCO

CONSOLIDATED STATEMENT OF INCOME (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Limited partners' net income per unit, basic and diluted (Note I)	$0.54	$0.62	$1.35	$1.03
Interest Costs, Capitalized During Period	$14,303	$14,320	$41,446	$38,284

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Other comprehensive income (loss)	'	'	'	'
Net income	$167,320	$216,400	$647,299	$575,539
Unrealized gains (losses) on derivatives	7,378	-3,596	-81,592	38,786
Realized (gains) losses on derivatives recognized in net income	3,003	2,204	39,845	3,273
Total other comprehensive income (loss)	10,381	-1,392	-41,747	42,059
Comprehensive income	177,701	215,008	605,552	617,598
Less: Comprehensive income attributable to noncontrolling interests	73	90	226	263
Comprehensive income attributable to ONEOK Partners, L.P.	$177,628	$214,918	$605,326	$617,335

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets	'	'
Cash and cash equivalents	$54,029	$134,530
Accounts receivable, net	951,647	1,103,130
Affiliate receivables	5,929	9,185
Natural gas and natural gas liquids in storage	338,345	188,286
Commodity imbalances	74,247	80,481
Other current assets	83,773	67,491
Total current assets	1,507,970	1,583,103
Property, plant and equipment	'	'
Property, plant and equipment	11,951,450	10,755,048
Accumulated depreciation and amortization	1,837,105	1,652,648
Net property, plant and equipment	10,114,345	9,102,400
Investments and other assets	'	'
Investments in unconsolidated affiliates (Note J)	1,128,509	1,229,838
Goodwill and intangible assets	825,333	832,180
Other assets	78,085	115,087
Total investments and other assets	2,031,927	2,177,105
Total assets	13,654,242	12,862,608
Current liabilities	'	'
Current maturities of long-term debt	7,650	7,650
Notes payable (Note E)	0	0
Accounts payable	1,216,107	1,255,411
Affiliate payables	29,382	47,458
Commodity imbalances	171,249	213,577
Accrued interest	88,048	92,711
Other current liabilities	159,341	89,211
Total current liabilities	1,671,777	1,706,018
Long-term debt, excluding current maturities	6,039,997	6,044,867
Deferred credits and other liabilities	131,799	113,027
Commitments and contingencies (Note L)	'	'
ONEOK Partners, L.P. partners' equity:	'	'
General partner	204,110	170,561
Common units: 177,354,481 and 159,007,854 units issued and outstanding at September 30, 2014, and December 31, 2013, respectively	4,320,934	3,459,920
Class B units: 72,988,252 units issued and outstanding at September 30, 2014, and December 31, 2013	1,381,800	1,422,516
Accumulated other comprehensive loss (Note H)	-100,584	-58,837
Total ONEOK Partners, L.P. partners' equity	5,806,260	4,994,160
Noncontrolling interests in consolidated subsidiaries	4,409	4,536
Total equity	5,810,669	4,998,696
Total liabilities and equity	$13,654,242	$12,862,608

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical)	Sep. 30, 2014	Dec. 31, 2013
ONEOK Partners, L.P. partners equity:	'	'
Common units issued (in shares)	177,354,481	159,007,854
Common units outstanding (in shares)	177,354,481	159,007,854
Class B units issued (in shares)	72,988,252	72,988,252
Class B units outstanding (in shares)	72,988,252	72,988,252

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Operating activities	'	'
Net income	$647,299	$575,539
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	212,083	174,086
Allowance for equity funds used during construction	-13,947	-21,172
Loss (gain) on sale of assets	-1,533	-342
Deferred income taxes	4,397	5,673
Equity earnings from investments	-6,747	-79,744
Distributions received from unconsolidated affiliates	84,298	79,022
Changes in assets and liabilities:	'	'
Accounts receivable	159,829	-42,539
Affiliate receivables	3,256	2,865
Natural gas and natural gas liquids in storage	-150,059	-154,793
Accounts payable	-33,945	171,770
Affiliate payables	-18,076	-31,776
Commodity imbalances, net	-36,094	-48,984
Accrued interest	-4,663	11,811
Other assets and liabilities, net	40,957	12,702
Cash provided by operating activities	887,055	654,118
Investing activities	'	'
Capital expenditures (less allowance for equity funds used during construction)	-1,172,950	-1,373,904
Acquisition	-14,000	-304,889
Contributions to unconsolidated affiliates	-1,063	-4,558
Distributions received from unconsolidated affiliates	24,925	24,891
Proceeds from sale of assets	2,388	641
Cash used in investing activities	-1,160,700	-1,657,819
Financing activities	'	'
Cash distributions: general and limited partners	-768,094	-669,981
Cash distributions: noncontrolling interests	-353	-442
Borrowing of notes payable, net	0	47,000
Issuance of long-term debt, net of discounts	0	1,247,822
Long-term debt financing costs	0	-10,217
Repayment of long-term debt	-5,738	-5,738
Issuance of common units, net of issuance costs	947,472	569,246
Contribution from general partner	19,857	11,967
Cash provided by financing activities	193,144	1,189,657
Change in cash and cash equivalents	-80,501	185,956
Cash and cash equivalents at beginning of period	134,530	537,074
Cash and cash equivalents at end of period	$54,029	$723,030

CONSOLIDATED_STATEMENT_OF_CHAN

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (USD $)	Total	Common Units [Member]	Class B Units [Member]	General Partner [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests in Consolidated Subsidiaries [Member]
In Thousands, except Share data
Partners capital account, beginning balance at Dec. 31, 2013	$4,998,696	$3,459,920	$1,422,516	$170,561	($58,837)	$4,536
Partners capital account, units, beginning balance at Dec. 31, 2013	'	159,007,854	72,988,252	'	'	'
Net income	647,299	274,963	122,413	249,697	0	226
Other comprehensive income (loss) (Note H)	-41,747	0	0	0	-41,747	0
Issuance of common units (in units) (Note G)	'	18,346,627	0	'	'	'
Issuance of common units (Note G)	955,108	955,108	0	0	0	0
Contribution from general partner (Note G)	19,760	0	0	19,760	0	0
Distributions paid (Note G)	-768,447	-369,057	-163,129	-235,908	0	-353
Partners capital account, ending balance at Sep. 30, 2014	$5,810,669	$4,320,934	$1,381,800	$204,110	($100,584)	$4,409
Partners capital account, units, ending balance at Sep. 30, 2014	'	177,354,481	72,988,252	'	'	'

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	'
	A.	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Our accompanying unaudited consolidated financial statements have been prepared pursuant to the rules and regulations of the SEC. These statements have been prepared in accordance with GAAP and reflect all adjustments that, in our opinion, are necessary for a fair presentation of the results for the interim periods presented.  All such adjustments are of a normal recurring nature. The 2013 year-end consolidated balance sheet data was derived from our audited financial statements but does not include all disclosures required by GAAP.  These unaudited consolidated financial statements should be read in conjunction with our audited consolidated financial statements in our Annual Report.
	Our significant accounting policies are consistent with those disclosed in Note A of the Notes to Consolidated Financial Statements in our Annual Report.
	Recently Issued Accounting Standards Update - In April 2014, the FASB issued ASU 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity,” which alters the definition of a discontinued operation to include only asset disposals that represent a strategic shift with a major effect on an entity's operations and financial results.  The amendments also require more extensive disclosures about a discontinued operation's assets, liabilities, income, expenses and cash flows. This guidance will be effective for interim and annual periods for all assets that are disposed of, or classified as being held for sale, in fiscal years that begin on or after December 15, 2014. We will adopt this guidance beginning in the first quarter 2015, and it could impact us in the future if we dispose of any individually significant components.
	In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which outlines the principles an entity must apply to measure and recognize revenue for entities that enter into contracts to provide goods or services to their customers. The core principle is that an entity should recognize revenue at an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring goods or services to a customer. The amendments also require more extensive disaggregated revenue disclosures in interim and annual financial statements. This update will be effective for interim and annual periods that begin on or after December 15, 2016, with either retrospective application for all periods presented or retrospective application with a cumulative effect adjustment. We will adopt this guidance beginning in the first quarter 2017, and we are evaluating the impact on us.
	In August 2014, the FASB issued ASU 2014-15, “Going Concern,” which provides guidance on determining when and how to disclose going-concern uncertainties in the financial statements. The new standard requires management to perform interim and annual assessments of an entity’s ability to continue as a going concern within one year of the date the financial statements are issued. An entity must provide certain disclosures if conditions or events raise substantial doubt about the entity’s ability to continue as a going concern. The standard applies to all entities and is effective for annual periods ending after December 15, 2016, and interim periods thereafter, with early adoption permitted. We will adopt this guidance beginning in the first quarter 2017, and we do not expect it to materially impact us.

ACQUISITIONS_ACQUISITIONS

ACQUISITIONS ACQUISITIONS	9 Months Ended
	Sep. 30, 2014
Acquired Finite-Lived Intangible Assets [Line Items]	'
Mergers, Acquisitions and Dispositions Disclosures [Text Block]	'
	B.	ACQUISITIONS
	West Texas LPG Acquisition - In October 2014, we announced that we have agreed to acquire an 80 percent interest in the West Texas LPG Limited Partnership (West Texas LPG) and 100 percent interest in the Mesquite Pipeline (Mesquite) from affiliates of Chevron Corporation for approximately $800 million, subject to customary post-closing adjustments. Closing is subject to customary conditions, including antitrust clearance from the Federal Trade Commission under the Hart-Scott-Rodino Act. Following the closing of the transaction, we will be the operator of both pipelines. Financing to close this transaction is expected to come from available cash on hand or borrowing under our existing $1.7 billion commercial paper program or existing $1.7 billion credit facility. We expect to account for this transaction using the acquisition method of accounting, which requires, among other things, that the asset acquired and liabilities assumed, which could include intangible assets and goodwill, be recognized on the balance sheet at their fair values as of the acquisition date.
	The West Texas LPG and Mesquite systems consist of approximately 2,600 miles of NGL gathering pipelines extending from the Permian Basin in southeastern New Mexico to East Texas and Mont Belvieu, Texas. The West Texas LPG and Mesquite systems are expected to provide us additional fee-based earnings and our NGL infrastructure with access to a new NGL supply basin.  The pipelines are expected to initially add an additional 230,000 bpd of unfractionated NGLs to our expanding NGL systems. The West Texas LPG and Mesquite pipelines access NGL supply from producers actively developing the Delaware, Midland and Central Basins in the Permian Basin, in addition to the Barnett Shale, East Texas and north Louisiana regions.
	Sage Creek Acquisition - On September 30, 2013, we completed the acquisition for $305 million of certain natural gas gathering and processing, and natural gas liquids facilities in Converse and Campbell counties, Wyoming, in the NGL-rich Niobrara Shale area 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.
	We 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. We allocated $152 million to our Natural Gas Gathering and Processing segment, and we allocated $153 million to our Natural Gas Liquids Segment. The excess of the purchase price over the fair values of the identifiable assets acquired of $92 million was recorded as goodwill.
	Revenues and earnings related to the Sage Creek acquisition are included within the Consolidated Statement of Income since the acquisition date. 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 the accompanying Consolidated Statement of Income and are, therefore, not presented.

FAIR_VALUE_MEASUREMENTS

FAIR VALUE MEASUREMENTS	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
FAIR VALUE MEASUREMENTS	'
	C.	FAIR VALUE MEASUREMENTS
	Determining Fair Value - 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 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 groups 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.  For certain transactions, we utilize modeling techniques using NYMEX-settled pricing data and implied forward LIBOR curves.  Inputs into our fair value estimates include commodity-exchange prices, over-the-counter quotes, 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 monitoring 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 are 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 - fair value measurements are based on unadjusted quoted prices in active markets including NYMEX-settled prices. These balances are comprised predominantly of exchange-traded derivative contracts for natural gas and crude oil.
	•	Level 2 - fair value measurements 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.
	•	Level 3 - fair value measurements 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. 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.
	Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements for the periods indicated:
		September 30, 2014
		Level 1			Level 2			Level 3			Total - Gross			Netting (a)			Total - Net (b)
		(Thousands of dollars)
	Derivatives assets
	Commodity contracts
	Financial contracts	$	9,093		$	439		$	—		$	9,532		$	(3,004	)	$	6,528
	Physical contracts	—			—			2,900			2,900			(329		)	2,571
	Interest-rate contracts	—			20,962			—			20,962			—			20,962
	Total derivative assets	$	9,093		$	21,401		$	2,900		$	33,394		$	(3,333	)	$	30,061
	Derivatives liabilities
	Commodity contracts
	Financial contracts	$	(83	)	$	—		$	(2,921	)	$	(3,004	)	$	3,004		$	—
	Physical contracts	—			—			(683		)	(683		)	329			(354		)
	Interest-rate contracts	—			(23,308		)	—			(23,308		)	—			(23,308		)
	Total derivative liabilities	$	(83	)	$	(23,308	)	$	(3,604	)	$	(26,995	)	$	3,333		$	(23,662	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis.  We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At September 30, 2014, we had no cash collateral held or posted.
	(b) - Included in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.
		December 31, 2013
		Level 1			Level 2			Level 3			Total - Gross			Netting (a)			Total - Net (b)
		(Thousands of dollars)
	Derivatives assets
	Commodity contracts
	Financial contracts	$	—		$	3,657		$	2,812		$	6,469		$	(1,746	)	$	4,723
	Physical contracts	—			—			2,023			2,023			(946		)	1,077
	Interest-rate contracts	—			54,503			—			54,503			—			54,503
	Total derivative assets	$	—		$	58,160		$	4,835		$	62,995		$	(2,692	)	$	60,303
	Derivatives liabilities
	Commodity contracts
	Financial contracts	$	—		$	(2,953	)	$	(2,154	)	$	(5,107	)	$	1,746		$	(3,361	)
	Physical contracts	—			—			(3,463		)	(3,463		)	946			(2,517		)
	Total derivative liabilities	$	—		$	(2,953	)	$	(5,617	)	$	(8,570	)	$	2,692		$	(5,878	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis.  We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2013, we had no cash collateral held or posted.
	(b) - Included in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.
	The following table sets forth a reconciliation of our Level 3 fair value measurements for the periods indicated:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	Derivative Assets (Liabilities)	2014			2013			2014			2013
		(Thousands of dollars)
	Net assets (liabilities) at beginning of period	$	(1,313	)	$	7,682		$	(782	)	$	(2,423	)
	Total realized/unrealized gains (losses):
	Included in earnings (a)	207			—			(688		)	—
	Included in other comprehensive income (loss)	402			(7,181		)	(2,968		)	2,924
	Purchases, issuances and settlements	—			—			3,734			—
	Net assets (liabilities) at end of period	$	(704	)	$	501		$	(704	)	$	501
	(a) - Included in commodity sales revenues in our Consolidated Statements of Income.
	Realized/unrealized gains (losses) include the realization of our derivative contracts through maturity. During the three and nine months ended September 30, 2014 and 2013, gains or losses included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the end of the period were not material.
	We recognize transfers into and out of the levels in the fair value hierarchy as of the end of each reporting period. During the three and nine months ended September 30, 2014 and 2013, there were no transfers between levels.
	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 the aggregate of our senior notes outstanding, including current maturities, was $6.7 billion and $6.5 billion at September 30, 2014, and December 31, 2013, respectively.  The book value of the aggregate of our senior notes outstanding, including current maturities, was $6.0 billion and $6.1 billion at September 30, 2014, and December 31, 2013, respectively.  The estimated fair value of the aggregate of our senior notes outstanding was determined using quoted market prices for similar issues with similar terms and maturities.  The estimated fair value of our long-term debt is classified as Level 2.
	During the three months ended September 30, 2014, we recorded a noncash impairment to our equity investment in Bighorn Gas Gathering. The valuation of this investment required use of significant unobservable inputs. We used an income approach to estimate the fair value of our investment. Our discounted cash flow analysis included the following inputs that are not readily available: a discount rate reflective of our cost of capital and estimated contract rates, volumes, operating and maintenance costs and capital expenditures. The estimated fair value of this investment is classified as Level 3.  See Note J for additional information about our investment in Bighorn Gas Gathering and the impairment charge.

RISK_MANAGEMENT_AND_HEDGING_AC

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES	'
	D.	RISK-MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES
	Risk-Management Activities - We are sensitive to changes in natural gas, crude oil and NGL prices, principally as a result of contractual terms under which these commodities are processed, purchased and sold.  We use physical-forward sales and financial derivatives to secure a certain price for a portion of our natural gas, condensate and NGL products.  We follow established policies and procedures to assess risk and approve, monitor and report our risk-management activities.  We have not used these instruments for trading purposes.  We are also subject to the risk of interest-rate fluctuation in the normal course of business.
	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, crude oil and condensate.  We use the following commodity derivative instruments to mitigate the commodity-price risk associated with a portion of the forecasted sales of these commodities:
	•	Futures contracts - Standardized contracts to purchase or sell natural gas and crude oil for future delivery or settlement under the provisions of exchange regulations;
	•	Forward contracts - Nonstandardized commitments between two parties to purchase or sell natural gas, crude oil or NGLs for future physical delivery. These contracts typically are nontransferable and only can be canceled with the consent of both parties; and
	•	Swaps - Exchange of one or more payments based on the value of one or more commodities. These instruments transfer the financial risk associated with a future change in value between the counterparties of the transaction, without also conveying ownership interest in the asset or liability.
	In our Natural Gas Gathering and Processing segment, we are exposed to commodity-price risk as a result of receiving commodities in exchange for services associated with our POP contracts. We are also exposed to basis risk between the various production and market locations where we receive and sell commodities.  As part of our hedging strategy, we use the previously described commodity derivative financial instruments and physical-forward contracts to minimize the impact of price fluctuations related to natural gas, NGLs and condensate.
	In our Natural Gas Liquids segment, we are exposed to basis risk primarily as a result of the relative value of NGL purchases at one location and sales at another location. To a lesser extent, we are exposed to commodity-price risk resulting from the relative values of the various NGL products to each other, NGLs in storage and the relative value of NGLs to natural gas. We utilize physical-forward contracts to reduce the impact of price fluctuations related to NGLs. At September 30, 2014, and December 31, 2013, there were no financial derivative instruments used in our natural gas liquids operations.
	In our Natural Gas Pipelines segment, we are exposed to commodity-price risk because our intrastate and interstate natural gas pipelines retain natural gas from our customers for operations or as part of our fee for services provided. When the amount of natural gas consumed as fuel in operations by these pipelines differs from the amount provided by our customers, our pipelines must buy or sell natural gas, or store or use natural gas from inventory, which can expose us to commodity-price risk depending on the regulatory treatment for this activity. To the extent that commodity-price risk in our Natural Gas Pipelines segment is not mitigated by fuel cost-recovery mechanisms, we use physical-forward sales or purchases to reduce the impact of price fluctuations related to natural gas. At September 30, 2014, and December 31, 2013, there were no financial derivative instruments used in our natural gas pipeline operations.
	Interest-rate risk - We manage interest-rate risk through the use of fixed-rate debt, floating-rate debt and interest-rate swaps. Interest-rate swaps are agreements to exchange interest payments at some future point based on specified notional amounts. At September 30, 2014, we had forward-starting interest-rate swaps with notional amounts totaling $900 million that have been 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, of which $400 million have settlement dates greater than 12 months.
	Accounting Treatment - 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.
	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 normal sales	-	Fair value not recorded	-	Change in fair value not recognized in earnings
	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		derivative instrument is reclassified out of
			as a 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
	Under certain conditions, we designate our derivative instruments as a hedge of exposure to changes in fair values or cash flows. 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 forecasted transaction that has been designated as the hedged item in a cash flow hedge relationship.  We assess the effectiveness of hedging relationships quarterly by performing an effectiveness analysis on our fair value and cash flow 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 realized revenues and purchase costs of our derivative instruments not considered held for trading purposes and derivatives that qualify as normal purchases or normal sales that are expected to result in physical delivery are reported on a gross basis.
	Cash flows from futures, forwards 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.
	Fair Values of Derivative Instruments - See Note C for a discussion of the inputs associated with our fair value measurements. The following table sets forth the fair values of our derivative instruments:
		September 30, 2014								December 31, 2013
		Assets (a)				(Liabilities) (a)				Assets (a)				(Liabilities) (a)
		(Thousands of dollars)
	Derivatives designated as hedging instruments
	Commodity contracts
	Financial contracts	$	9,532			$	(3,004	)		$	6,469			$	(5,107	)
	Physical contracts	2,554				(608		)		1,064				(3,463		)
	Interest-rate contracts	20,962				(23,308		)		54,503				—
	Total derivatives designated as hedging instruments	$	33,048			$	(26,920	)		$	62,036			$	(8,570	)
	Derivatives not designated as hedging instruments
	Commodity contracts
	Physical contracts	346				(75		)		959				—
	Total derivatives not designated as hedging instruments	346				(75		)		959				—
	Total derivatives	$	33,394			$	(26,995	)		$	62,995			$	(8,570	)
	(a) - Included on a net basis in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.
	Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for derivative instruments designated as hedging instruments for the periods indicated:
			30-Sep-14								December 31, 2013
		Contract	Purchased/				Sold/				Purchased/				Sold/
		Type	Payor				Receiver				Payor				Receiver
	Derivatives designated as hedging instruments:
	Cash flow hedges
	Fixed price
	- Natural gas (Bcf)	Futures and swaps	—				(31.2		)		—				(48.1		)
	- Crude oil and NGLs (MMBbl)	Futures, forwards	—				(1.7		)		—				(4.0		)
		and swaps
	Basis
	- Natural gas (Bcf)	Futures and swaps	—				(31.2		)		—				(48.1		)
	Interest-rate contracts (Millions of dollars)	Forward-starting	$	900			$	—			$	400			$	—
		swaps
	These notional quantities 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 - At September 30, 2014, our Consolidated Balance Sheet reflected a net unrealized loss of $100.6 million in accumulated other comprehensive income (loss).  The portion of accumulated other comprehensive income (loss) attributable to our commodity derivative instruments is a gain of $6.3 million, which will be realized within the next 15 months as the forecasted transactions affect earnings. If commodity prices remain at the current levels, we will recognize $5.4 million in gains over the next 12 months and $0.9 million in gains thereafter.  The amount deferred in accumulated other comprehensive income (loss) attributable to our settled interest-rate swaps is a loss of $102.0 million, which will be recognized over the life of the long-term, fixed-rate debt. We expect that losses of $10.6 million 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 forward-starting interest-rate swaps with future settlement dates, which will be amortized to interest expense over the life of long-term, fixed-rate debt upon issuance of the debt.
	The following table sets forth the effect of cash flow hedges recognized in other comprehensive income (loss) for the periods indicated:
	Three Months Ended								Nine Months Ended
Derivatives in Cash Flow	September 30,								September 30,
Hedging Relationships	2014				2013				2014				2013
	(Thousands of dollars)
Commodity contracts	$	17,133			$	(10,317	)		$	(24,743	)		$	3,060
Interest-rate contracts	(9,755		)		6,721				(56,849		)		35,726
Total unrealized gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion)	$	7,378			$	(3,596	)		$	(81,592	)		$	38,786
The following table sets forth the effect of cash flow hedges in our Consolidated Statements of Income for the periods indicated:
Derivatives in Cash Flow	Location of Gain (Loss) Reclassified from	Three Months Ended								Nine Months Ended
Hedging Relationships	Accumulated Other Comprehensive Income	September 30,								September 30,
	(Loss) into Net Income (Effective Portion)	2014				2013				2014				2013
		(Thousands of dollars)
Commodity contracts	Commodity sales revenues	$	(355	)		$	361			$	(31,961	)		$	4,172
Interest-rate contracts	Interest expense	(2,648		)		(2,565		)		(7,884		)		(7,445		)
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income on derivatives (effective portion)		$	(3,003	)		$	(2,204	)		$	(39,845	)		$	(3,273	)
Ineffectiveness related to our cash flow hedges was not material for the three and nine months ended September 30, 2014 and 2013. In the event that it becomes probable that a forecasted transaction will not occur, we would discontinue cash flow hedge treatment, which would affect earnings.  There were no gains or losses due to the discontinuance of cash flow hedge treatment during the three and nine months ended September 30, 2014 and 2013.
Credit Risk - Prior to March 31, 2014, all of our commodity derivative financial contracts were with our affiliate ONEOK Energy Services Company, a subsidiary of ONEOK. ONEOK Energy Services Company entered into similar commodity derivative financial contracts with third parties at our direction and on our behalf. On March 31, 2014, ONEOK completed the accelerated wind down of ONEOK Energy Services Company. In the first quarter 2014, outstanding commodity derivative positions with third parties entered into by ONEOK Energy Services Company on our behalf were transferred to us. Beginning in the second quarter 2014, we enter into all commodity derivative financial contracts directly with unaffiliated third parties.
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 financial 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 our senior unsecured long-term debt were to decline below investment grade, the counterparties to the derivative instruments could request collateralization on derivative instruments in net liability positions. There were no financial derivative instruments with contingent features related to credit risk that were in a net liability position at September 30, 2014.
The counterparties to our derivative contracts consist primarily of major energy companies, financial institutions and commercial and industrial end users.  This concentration of counterparties may affect our overall exposure to credit risk, either positively or negatively, in that the counterparties may be affected similarly by changes in economic, regulatory or other conditions.  Based on our policies, exposures, credit and other reserves, we do not anticipate a material adverse effect on our financial position or results of operations as a result of counterparty nonperformance.

CREDIT_FACILITY_AND_SHORTTERM_

CREDIT FACILITY AND SHORT-TERM NOTES PAYABLE	9 Months Ended
	Sep. 30, 2014
Short-term Debt [Abstract]	'
CREDIT FACILITY AND SHORT-TERM NOTES PAYABLE	'
	E.	CREDIT FACILITY AND SHORT-TERM NOTES PAYABLE
	Partnership Credit Agreement - The amount of short-term borrowings authorized by our general partner’s Board of Directors is $2.5 billion. At September 30, 2014, we had no commercial paper outstanding, $14.0 million in letters of credit issued and no borrowings under our Partnership Credit Agreement.
	Our Partnership Credit Agreement, which was amended and restated effective on January 31, 2014, and expires in January 2019, is a $1.7 billion revolving credit facility and 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 by either commitments from new lenders or increased commitments from existing lenders. Our Partnership Credit Agreement is available for general partnership purposes. During the second quarter 2014, we increased the size of our commercial paper program to $1.7 billion from $1.2 billion. Amounts outstanding under our commercial paper program reduce the borrowing capacity under our Partnership Credit Agreement.
	Our Partnership 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 ratings, borrowings, if any, will accrue at LIBOR plus 117.5 basis points, and the annual facility fee is 20 basis points. Our Partnership Credit Agreement is guaranteed fully and unconditionally by the Intermediate Partnership. Borrowings under our Partnership Credit Agreement are nonrecourse to ONEOK, and ONEOK does not guarantee our debt, commercial paper or other similar commitments.
	Our Partnership Credit Agreement contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in our Partnership 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 we consummate 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 in which the acquisition was completed and the two following quarters.  As a result of a pipeline acquisition we completed in the first quarter 2014, the allowable ratio of indebtedness to adjusted EBITDA increased to 5.5 to 1 through the third quarter 2014. Upon breach of certain covenants by us in our Partnership Credit Agreement, amounts outstanding under our Partnership Credit Agreement, if any, may become due and payable immediately.  At September 30, 2014, our ratio of indebtedness to adjusted EBITDA was 3.4 to 1, and we were in compliance with all covenants under our Partnership Credit Agreement.

LONG_TERM_DEBT_LONGTERM_DEBT_N

LONG TERM DEBT LONG-TERM DEBT (Notes)	9 Months Ended
	Sep. 30, 2014
Debt Instrument [Line Items]	'
Long-term Debt [Text Block]	'
	F.	LONG-TERM DEBT
	In September 2013, we 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 our commercial paper program, and the balance was used for general partnership purposes, including but not limited to capital expenditures.

EQUITY

EQUITY	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
EQUITY	'
	G.	EQUITY
	ONEOK - ONEOK and its affiliates own all of the Class B units, 19.8 million common units and the entire 2 percent general partner interest in us, which together constituted a 38.3 percent ownership interest in us at September 30, 2014.
	Equity Issuances - In May 2014, we completed an underwritten public offering of approximately 13.9 million common units at a public offering price of $52.94 per common unit, generating net proceeds of approximately $714.5 million. In conjunction with this issuance, ONEOK Partners GP contributed approximately $15.0 million in order to maintain its 2 percent general partner interest in us. We used the proceeds to repay commercial paper, fund our capital expenditures and for general partnership purposes.
	We have an “at-the-market” equity program for the offer and sale from time to time of our common units. The program allows us to offer and sell our common units at prices we deem 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 us and the sales agent. We are under no obligation to offer and sell common units under the program.
	During the three months ended September 30, 2014, we sold approximately 1.4 million common units through the “at-the-market” equity program. The net proceeds, including ONEOK Partners GP’s contribution to maintain its 2 percent general partner interest in us, were approximately $81.3 million, which were used for general partnership purposes.
	During the nine months ended September 30, 2014, we sold approximately 4.4 million common units through this program. The net proceeds, including ONEOK Partners GP’s contribution to maintain its 2 percent general partner interest in us, were approximately $245.4 million, which were used for general partnership purposes.
	As a result of these transactions, ONEOK’s aggregate ownership interest in us decreased to 38.3 percent at September 30, 2014, from 41.2 percent at December 31, 2013.
	In August 2013, we 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 $553.4 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 us. We used a portion of the proceeds from our August 2013 equity issuance to repay amounts outstanding under our commercial paper program, and the balance was used for general partnership purposes.
	During the three months ended March 31, 2013, we sold 300,000 common units through the “at-the-market” program that resulted in net proceeds, including ONEOK Partners GP’s contribution to maintain its 2 percent general partner interest in us, of approximately $16.3 million and used the proceeds for general partnership purposes. There were no common units sold through this program in the second or third quarter 2013.
	Partnership Agreement - Available cash, as defined in our Partnership Agreement, generally will be distributed to our general partner and limited partners according to their partnership percentages of 2 percent and 98 percent, respectively. Our general partner’s percentage interest in quarterly distributions is increased after certain specified target levels are met during the quarter. Under the incentive distribution provisions, as set forth in our Partnership Agreement, our 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.
	Cash Distributions - In October 2014, our general partner declared a cash distribution of $0.775 per unit ($3.10 per unit on an annualized basis) for the third quarter 2014, an increase of 1.5 cents from the previous quarter, which will be paid on November 14, 2014, to unitholders of record at the close of business on November 3, 2014.
	The following table shows our distributions paid in the periods indicated:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2014		2013		2014		2013
		(Thousands, except per unit amounts)
	Distribution per unit	$	0.76	$	0.72	$	2.235	$	2.145
	General partner distributions	$	5,501	$	4,512	$	15,361	$	13,399
	Incentive distributions	80,381		62,634		220,547		184,647
	Distributions to general partner	85,882		67,146		235,908		198,046
	Limited partner distributions to ONEOK	70,519		66,807		207,381		199,031
	Limited partner distributions to other unitholders	118,644		91,676		324,805		272,904
	Total distributions paid	$	275,045	$	225,629	$	768,094	$	669,981
	The following table shows our distributions declared for the periods indicated and paid within 45 days of the end of the period:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2014		2013		2014		2013
		(Thousands, except per unit amounts)
	Distribution per unit	$	0.775	$	0.725	$	2.28	$	2.16
	General partner distributions	$	5,683	$	4,795	$	16,195	$	13,776
	Incentive distributions	84,452		67,017		236,744		191,226
	Distributions to general partner	90,135		71,812		252,939		205,002
	Limited partner distributions to ONEOK	71,911		67,271		211,557		200,422
	Limited partner distributions to other unitholders	122,105		100,650		345,255		283,365
	Total distributions declared	$	284,151	$	239,733	$	809,751	$	688,789

ACCUMULATED_OTHER_COMPREHENSIV

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) ACCUMULATED OTHER COMPREHENSIVE INCOME (Notes)	9 Months Ended
	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Abstract]	'
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	'
	H.	ACCUMULATED OTHER COMPREHENSIVE LOSS
	The following table sets forth the balance in accumulated other comprehensive income (loss) for the period indicated:
			Accumulated
			Other
			Comprehensive
			Loss (a)
			(Thousands of dollars)
	1-Jan-14		$	(58,837	)
	Other comprehensive income (loss) before classifications		(81,592		)
	Amounts reclassified from accumulated other comprehensive income (loss)		39,845
	Net current-period other comprehensive income (loss) attributable to ONEOK Partners		(41,747		)
	September 30, 2014		$	(100,584	)
	(a) All amounts are attributable to unrealized gains (losses) in risk-management assets/liabilities.
	The following table sets forth the effect of reclassifications from accumulated other comprehensive income (loss) in our Consolidated Statements of Income for the periods indicated:
	Details about Accumulated Other		Three Months Ended						Nine Months Ended					Affected Line Item in the
	Comprehensive Income (Loss) Components		September 30,						September 30,					Consolidated Statements of Income
			2014			2013			2014		2013
			(Thousands of dollars)
	Unrealized (gains) losses on risk-management assets/liabilities
	Commodity contracts		$	355		$	(361	)	$	31,961	$	(4,172	)	Commodity sales revenues
	Interest-rate contracts		2,648			2,565			7,884		7,445			Interest expense
	Total reclassifications for the period attributable to ONEOK Partners		$	3,003		$	2,204		$	39,845	$	3,273		Net income attributable to ONEOK Partners

LIMITED_PARTNERS_NET_INCOME_PE

LIMITED PARTNERS' NET INCOME PER UNIT	9 Months Ended
	Sep. 30, 2014
Limited Partners' Net Income Per Unit and Distributions to Partners [Abstract]	'
LIMITED PARTNERS' NET INCOME PER UNIT	'
	I.	LIMITED PARTNERS’ NET INCOME PER UNIT
	Limited partners’ net income per unit is computed by dividing net income attributable to ONEOK Partners, L.P., after deducting the general partner’s allocation as discussed below, by the weighted-average number of outstanding limited partner units, which includes our common and Class B limited partner units.  Because ONEOK has waived conditionally its right to increased quarterly distributions, until it gives 90 days notice of the withdrawal of the waiver, each Class B unit and common unit currently share equally in the earnings of the partnership, and neither has any liquidation or other preferences.
	ONEOK Partners GP owns the entire 2 percent general partnership interest in us, which entitles it to incentive distribution rights that provide for an increasing proportion of cash distributions from the Partnership as the distributions made to limited partners increase above specified levels.  For purposes of our calculation of limited partners’ net income per unit, net income attributable to ONEOK Partners, L.P. is allocated to the general partner as follows:  (i) an amount based upon the 2 percent general partner interest in net income attributable to ONEOK Partners, L.P.; and (ii) the amount of the general partner’s incentive distribution rights based on the total cash distributions declared for the period.
	The terms of our Partnership Agreement limit the general partner’s incentive distribution to the amount of available cash calculated for the period.  As such, incentive distribution rights are not allocated on undistributed earnings or distributions in excess of earnings.  For additional information regarding our general partner’s incentive distribution rights, see “Partnership Agreement” in Note I of the Notes to Consolidated Financial Statements in our Annual Report.

UNCONSOLIDATED_AFFILIATES

UNCONSOLIDATED AFFILIATES	9 Months Ended
	Sep. 30, 2014
Equity Method Investments and Joint Ventures [Abstract]	'
UNCONSOLIDATED AFFILIATES	'
	J.	UNCONSOLIDATED AFFILIATES
	Equity Earnings from Investments - The following table sets forth our equity earnings (losses) from investments for the periods indicated:
		Three Months Ended					Nine Months Ended
		September 30,					September 30,
		2014			2013		2014			2013
		(Thousands of dollars)
	Share of investee earnings (loss)
	Northern Border Pipeline	$	14,371		$	16,464	$	53,657		$	48,133
	Overland Pass Pipeline Company	3,856			5,783		12,708			14,210
	Fort Union Gas Gathering	4,169			2,946		12,578			9,895
	Bighorn Gas Gathering (a)	(23,472		)	559		(24,745		)	1,897
	Other	2,150			1,716		5,970			5,609
	Total share of investee earnings	1,074			27,468		60,168			79,744
	Impairment of investment in Bighorn Gas Gathering	(53,421		)	—		(53,421		)	—
	Equity earnings (loss) from investments	$	(52,347	)	$	27,468	$	6,747		$	79,744
	(a) Includes proportionate share of investee impairment of long-lived assets charge of $23.0 million.
	Unconsolidated Affiliates Financial Information - The following table sets forth summarized combined financial information of our unconsolidated affiliates for the periods indicated:
		Three Months Ended					Nine Months Ended
		September 30,					September 30,
		2014			2013		2014			2013
		(Thousands of dollars)
	Income Statement
	Operating revenues	$	126,218		$	131,959	$	403,006		$	391,912
	Operating expenses (a)	$	123,620		$	63,971	$	247,169		$	189,366
	Net income (loss) (a)	$	(5,119	)	$	61,630	$	134,432		$	185,580
	Distributions paid to us	$	31,574		$	34,409	$	109,223		$	103,913
	(a) - Includes long-lived asset impairment charge on Bighorn Gas Gathering.
	We incurred expenses in transactions with unconsolidated affiliates of $15.0 million and $15.9 million for the three months ended September 30, 2014 and 2013, respectively, and $43.5 million and $36.3 million for the nine months ended September 30, 2014 and 2013, respectively, primarily related to Overland Pass Pipeline Company and Northern Border Pipeline Company, which are included in cost of sales and fuel in our Consolidated Statements of Income. Accounts payable to our equity method investees at September 30, 2014, and December 31, 2013, were not material.
	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 formations of the Powder River Basin have resulted in lower natural gas volumes available to be gathered.  While the reserve potential in the dry natural gas formations of the Powder River Basin still exists, future drilling and development will be affected by commodity prices and producers’ alternative prospects.
	During 2014 through the third quarter, the volumes gathered on the Bighorn Gas Gathering system declined at a rate greater than in prior periods and greater than expected. Due to these additional declines in volumes, Bighorn Gas Gathering recorded an impairment of its underlying assets in September 2014, when the operator determined that the volume decline was other than temporary. As a result of these developments, we reviewed our equity method investment in Bighorn Gas Gathering for impairment as of September 30, 2014. We recorded noncash impairment charges of $76.4 million related to Bighorn Gas Gathering. The noncash impairment charges are included in equity earnings (loss) from investments in our accompanying Consolidated Statements of Income. The remaining net book value of our equity method investment in Bighorn Gas Gathering is $8.8 million, and no equity method goodwill remains.

RELATEDPARTY_TRANSACTIONS

RELATED-PARTY TRANSACTIONS	9 Months Ended
	Sep. 30, 2014
Related Party Transactions [Abstract]	'
RELATED-PARTY TRANSACTIONS	'
	K.	RELATED-PARTY TRANSACTIONS
	Intersegment and affiliate sales are recorded on the same basis as sales to unaffiliated customers.  Prior to March 31, 2014, our Natural Gas Gathering and Processing segment sold natural gas to ONEOK and its subsidiaries, and our Natural Gas Pipelines segment provided transportation and storage services to ONEOK and its subsidiaries. Additionally, our Natural Gas Gathering and Processing segment and Natural Gas Liquids segment purchased a portion of the natural gas used in their operations from ONEOK and its subsidiaries.
	On January 31, 2014, ONEOK completed the separation of its former natural gas distribution business into ONE Gas. ONE Gas was an affiliate prior to this separation. Commodity sales and services revenues in the Consolidated Statements of Income for the one month ended January 31, 2014, and for the nine months ended September 30, 2013, for transactions with ONE Gas prior to the separation are reflected as affiliate transactions. Transactions with ONE Gas that occurred after the separation are reflected as unaffiliated, third-party transactions.
	On March 31, 2014, ONEOK completed the accelerated wind down of ONEOK Energy Services Company, a subsidiary of ONEOK. For the first quarter 2014 and the three and nine months ended September 30, 2013, we had transactions with ONEOK Energy Services Company, which are reflected as affiliate transactions.
	Under the Services Agreement with ONEOK and ONEOK Partners GP (the Services Agreement), our operations and the operations of ONEOK and its affiliates can combine or share certain common services in order to operate more efficiently and cost effectively.  Under the Services Agreement, ONEOK provides to us similar services that it provides to its affiliates, including those services required to be provided pursuant to our Partnership Agreement.  ONEOK Partners GP operates Guardian Pipeline, Viking Gas Transmission Company and Midwestern Gas Transmission Company according to each pipeline’s operating agreement. ONEOK Partners GP may purchase services from ONEOK and its affiliates pursuant to the terms of the Services Agreement. ONEOK Partners GP has no employees and utilizes the services of ONEOK to fulfill its operating obligations.
	ONEOK and its affiliates provide a variety of services to us under the Services Agreement, including cash management and financial services, employee benefits provided through ONEOK’s benefit plans, legal and administrative services, insurance and office space leased in ONEOK’s headquarters building and other field locations.  Where costs are incurred specifically on behalf of one of our affiliates, the costs are billed directly to us by ONEOK.  In other situations, the costs may be allocated to us through a variety of methods, depending upon the nature of the expense and activities. Beginning in the second quarter 2014, ONEOK allocates substantially all of its general overhead costs to us as a result of ONEOK’s separation of its natural gas distribution business and the wind down of its energy services business in the first quarter 2014.  For the first quarter 2014 and the three and nine months ended September 30, 2013, it is not practicable to determine what these general overhead costs would have been on a stand-alone basis.  All costs directly charged or allocated to us are included in our Consolidated Statements of Income.
	The following table sets forth the transactions with related parties for the periods indicated:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2014		2013		2014		2013
		(Thousands of dollars)
	Revenues	$	—	$	81,324	$	53,526	$	255,298
	Expenses
	Cost of sales and fuel	$	—	$	9,562	$	10,835	$	27,855
	Administrative and general expenses	84,221		58,549		240,172		192,906
	Total expenses	$	84,221	$	68,111	$	251,007	$	220,761
	ONEOK Partners GP made additional general partner contributions to us of approximately $19.8 million and $12.0 million during the nine months ended September 30, 2014 and 2013, respectively, to maintain its 2 percent general partner interest in connection with the issuances of common units.  See Note G for additional information about our equity issuances and cash distributions paid to ONEOK for its general partner and limited partner interests.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
COMMITMENTS AND CONTINGENCIES	'
	L.	COMMITMENTS AND CONTINGENCIES
	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, emission 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 (the President) issued the President’s Climate Action Plan, which includes, among other things, plans for further regulatory actions to reduce carbon emissions from various sources. On March 28, 2014, the President released the Climate Action Plan - Strategy to Reduce Methane Emissions (Methane Strategy) that lists a number of actions that the federal agencies will undertake to continue to reduce above-ground methane emissions from several industries, including the oil and natural gas sectors. The proposed measures outlined in the Methane Strategy include, without limitation, the following: collaboration with the states to encourage emission reductions; standards to minimize natural gas venting and flaring on public lands; policy recommendations for reducing emissions from energy infrastructure to increase the performance of the nation’s energy transmission, storage and distribution systems; and continued efforts by PHMSA to require pipeline operators to take steps to eliminate leaks and prevent accidental methane releases and evaluate the progress of states in replacing cast-iron pipelines. The impact of any such proposed regulatory actions on our facilities and operations is unknown. We continue to monitor these developments and the impact they may have on our businesses. 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.
	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 the three and nine months ended September 30, 2014, and 2013.
	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 (BACT), conduct air-quality and impact analysis and public reviews with respect to such emissions. At current emission threshold levels, this rule has had a minimal impact on our existing facilities. In addition, on June 23, 2014, the Supreme Court of the United States, in a case styled, Utility Air Regulatory Group v. EPA, 530 U.S. (2014), held that an industrial facility’s potential to emit greenhouse gas (GHG) emissions alone cannot subject a facility to the permitting requirements for major stationary source provisions of the Clean Air Act. The decision invalidated the EPA’s current Triggering and Tailoring Rule for GHG Prevention of Significant Deterioration (PSD) and Title V requirements as applied to facilities considered major sources only for GHGs. However, the Court also ruled that to the extent a source pursues a capital project (new construction or expansion of existing facility), which otherwise subjects the source to major source PSD permitting for conventional criteria pollutants, the permitting authorities may impose BACT analysis and emission limits for GHGs from those sources. We are in the process of evaluating the effects the decision and related pending judicial proceedings at the lower court level may have on our existing operations and the opportunities it creates for design decisions for new project applications.
	In July 2011, the EPA issued a proposed rule that would change the air emission 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.
	The rule was most recently amended in September 2013, and a further proposed rule-making was published in July 2014. The EPA has indicated that further amendments may be issued in 2014. Based on the amendments, our understanding of pending stakeholder responses to the NSPS rule and the proposed rule-making, we do not anticipate a material impact to 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 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 asset 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.
	Legal Proceedings - We are a party to various litigation matters and claims that have arisen in the normal course of our operations.  While the results of litigation and claims cannot be predicted with certainty, we believe the reasonably possible losses from such matters, individually and in the aggregate, are not material.  Additionally, we believe the probable final outcome of such matters will not have a material adverse effect on our consolidated results of operations, financial position or cash flows.

SEGMENTS

SEGMENTS	9 Months Ended
	Sep. 30, 2014
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]	'
SEGMENTS	'
	M.	SEGMENTS
	Segment Descriptions - Our operations are divided into three reportable business segments, as follows:
	•	our Natural Gas Gathering and Processing segment gathers, treats and processes natural gas;
	•	our Natural Gas Liquids segment gathers, treats, fractionates and transports NGLs and stores, markets and distributes NGL products; and
	•	our Natural Gas Pipelines segment operates regulated interstate and intrastate natural gas transmission pipelines and natural gas storage facilities.
	Accounting Policies - We evaluate performance based principally on each segment’s operating income and equity earnings. The accounting policies of the segments are described in Note A of the Notes to Consolidated Financial Statements in our Annual Report. Affiliate and intersegment sales are recorded on the same basis as sales to unaffiliated customers.  Net margin is comprised of total revenues less cost of sales and fuel.  Cost of sales and fuel includes commodity purchases, fuel, storage and transportation costs.
	As a result of ONEOK’s separation of its natural gas distribution business into a stand-alone publicly traded company called ONE Gas on January 31, 2014, transactions with ONE Gas subsequent to the separation are reflected as sales to unaffiliated customers.
	Customers - The primary customers of our Natural Gas Gathering and Processing segment are major and independent crude oil and natural gas production companies.  Our Natural Gas Liquids segment’s customers are primarily NGL and natural gas gathering and processing companies, major and independent crude oil and natural gas production companies, propane distributors, ethanol producers and petrochemical, refining and NGL marketing companies. Natural Gas Pipelines segment customers include natural gas distribution, electric-generation, natural gas marketing, industrial and major and independent crude oil and natural gas production companies.
	For the three and nine months ended September 30, 2014 and 2013, we had no single customer from which we received 10 percent or more of our consolidated revenues.
	Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated:
	Three Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-14	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	374,403		$	2,667,939		$	77,027		$	—		$	3,119,369
	Intersegment revenues	403,399			66,581			2,133			(472,113		)	—
	Total revenues	$	777,802		$	2,734,520		$	79,160		$	(472,113	)	$	3,119,369
	Net margin	$	178,171		$	282,963		$	73,399		$	1,632		$	536,165
	Operating costs	64,279			76,946			27,998			1,562			170,785
	Depreciation and amortization	31,327			31,661			10,913			—			73,901
	Gain (loss) on sale of assets	324			(535		)	1,746			(1		)	1,534
	Operating income	$	82,889		$	173,821		$	36,234		$	69		$	293,013
	Equity earnings (loss) from investments	$	(71,069	)	$	4,351		$	14,371		$	—		$	(52,347	)
	Capital expenditures	$	214,917		$	153,785		$	10,650		$	1,184		$	380,536
	(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $190.3 million, of which $170.1 million was related to sales within the segment, net margin of $94.3 million and operating income of $46.4 million.
	(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $65.2 million, net margin of $57.4 million and operating income of $23.4 million.
	Three Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-13	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	162,677		$	2,840,108		$	50,624		$	—		$	3,053,409
	Sales to affiliated customers	57,400			—			23,924			—			81,324
	Intersegment revenues	312,940			34,740			1,330			(349,010		)	—
	Total revenues	$	533,017		$	2,874,848		$	75,878		$	(349,010	)	$	3,134,733
	Net margin	$	130,882		$	226,242		$	69,457		$	(3,007	)	$	423,574
	Operating costs	45,074			57,010			23,457			(3,179		)	122,362
	Depreciation and amortization	27,356			22,993			10,833			—			61,182
	Gain (loss) on sale of assets	31			7			(16		)	—			22
	Operating income	$	58,483		$	146,246		$	35,151		$	172		$	240,052
	Equity earnings from investments	$	4,668		$	6,336		$	16,464		$	—		$	27,468
	Capital expenditures	$	204,542		$	230,780		$	11,148		$	2,602		$	449,072
	(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $147.1 million, of which $130.2 million was related to sales within the segment, net margin of $89.5 million and operating income of $53.4 million.
	(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $57.5 million, net margin of $52.8 million and operating income of $22.6 million.
	Nine Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-14	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	1,095,531		$	7,950,930		$	247,420		$	—		$	9,293,881
	Sales to affiliated customers	41,214			—			12,312			—			53,526
	Intersegment revenues	1,126,547			160,712			6,206			(1,293,465		)	—
	Total revenues	$	2,263,292		$	8,111,642		$	265,938		$	(1,293,465	)	$	9,347,407
	Net margin	$	486,695		$	818,086		$	242,359		$	(7,008	)	$	1,540,132
	Operating costs	188,489			218,129			82,747			(7,752		)	481,613
	Depreciation and amortization	89,612			89,848			32,623			—			212,083
	Gain (loss) on sale of assets	277			(572		)	1,663			165			1,533
	Operating income	$	208,871		$	509,537		$	128,652		$	909		$	847,969
	Equity earnings (loss) from investments	$	(60,484	)	$	13,574		$	53,657		$	—		$	6,747
	Investments in unconsolidated affiliates	$	253,930		$	484,238		$	390,341		$	—		$	1,128,509
	Total assets	$	4,415,814		$	7,337,688		$	1,832,368		$	68,372		$	13,654,242
	Noncontrolling interests in consolidated subsidiaries	$	4,394		$	—		$	—		$	15		$	4,409
	Capital expenditures	$	506,016		$	637,524		$	25,987		$	3,423		$	1,172,950
	(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $479.4 million, of which $417.0 million was related to sales within the segment, net margin of $263.4 million and operating income of $126.0 million.
	(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $214.8 million, net margin of $185.5 million and operating income of $84.6 million.
Nine Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
	Gathering and			Liquids (a)			Pipelines (b)			Eliminations
30-Sep-13	Processing
	(Thousands of dollars)
Sales to unaffiliated customers	$	466,631		$	7,539,470		$	158,960		$	—		$	8,165,061
Sales to affiliated customers	179,636			—			75,662			—			255,298
Intersegment revenues	806,523			91,161			2,327			(900,011		)	—
Total revenues	$	1,452,790		$	7,630,631		$	236,949		$	(900,011	)	$	8,420,359
Net margin	$	365,436		$	632,087		$	211,224		$	(2,621	)	$	1,206,126
Operating costs	141,737			171,076			75,608			(3,819		)	384,602
Depreciation and amortization	76,366			65,033			32,687			—			174,086
Gain (loss) on sale of assets	344			10			(12		)	—			342
Operating income	$	147,677		$	395,988		$	102,917		$	1,198		$	647,780
Equity earnings from investments	$	16,228		$	15,383		$	48,133		$	—		$	79,744
Investments in unconsolidated affiliates	$	331,124		$	494,702		$	376,047		$	—		$	1,201,873
Total assets	$	3,808,135		$	6,610,205		$	1,786,413		$	658,573		$	12,863,326
Noncontrolling interests in consolidated subsidiaries	$	4,574		$	—		$	—		$	14		$	4,588
Capital expenditures	$	574,509		$	774,284		$	22,497		$	2,614		$	1,373,904
(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $376.9 million, of which $321.3 million was related to sales within the segment, net margin of $227.8 million and operating income of $129.0 million.
(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $182.0 million, net margin of $162.5 million and operating income of $67.0 million.

SUPPLEMENTAL_CONDENSED_CONSOLI

SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION	9 Months Ended
	Sep. 30, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]	'
Supplemental Condensed Consolidating Financial Information	'
	N.	SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION
	We have no significant assets or operations other than our investment in our 100 percent owned subsidiary, the Intermediate Partnership.  The Intermediate Partnership holds all our partnership interests and equity in our subsidiaries, as well as a 50 percent interest in Northern Border Pipeline.  Our Intermediate Partnership guarantees our senior notes and borrowings, if any, under the Partnership Credit Agreement.  The Intermediate Partnership’s guarantees of our senior notes and of any borrowings under the Partnership Credit Agreement are full and unconditional, subject to certain customary automatic release provisions.
	For purposes of the following footnote:
	•	we are referred to as “Parent”;
	•	the Intermediate Partnership is referred to as “Guarantor Subsidiary”; and
	•	the “Non-Guarantor Subsidiaries” are all subsidiaries other than the Guarantor Subsidiary.
	The following unaudited supplemental condensed consolidating financial information is presented on an equity-method basis reflecting the Parent’s separate accounts, the Guarantor Subsidiary’s separate accounts, the combined accounts of the Non-Guarantor Subsidiaries, the combined consolidating adjustments and eliminations and the Parent’s consolidated amounts for the periods indicated.
	Condensed Consolidating Statements of Income
		Three Months Ended September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Revenues
	Commodity sales	$	—		$	—		$	2,754.50		$	—		$	2,754.50
	Services	—			—			364.9			—			364.9
	Total revenues	—			—			3,119.40			—			3,119.40
	Cost of sales and fuel	—			—			2,583.20			—			2,583.20
	Net margin	—			—			536.2			—			536.2
	Operating expenses
	Operations and maintenance	—			—			152.5			—			152.5
	Depreciation and amortization	—			—			73.9			—			73.9
	General taxes	—			—			18.3			—			18.3
	Total operating expenses	—			—			244.7			—			244.7
	Gain (loss) on sale of assets	—			—			1.5			—			1.5
	Operating income	—			—			293			—			293
	Equity earnings (loss) from investments	167.2			167.2			(66.7		)	(320.0		)	(52.3		)
	Allowance for equity funds used during	—			—			1.7			—			1.7
	construction
	Other income (expense), net	83.1			83.1			(2.4		)	(166.2		)	(2.4		)
	Interest expense, net	(83.1		)	(83.1		)	(70.1		)	166.2			(70.1		)
	Income before income taxes	167.2			167.2			155.5			(320.0		)	169.9
	Income taxes	—			—			(2.6		)	—			(2.6		)
	Net income	167.2			167.2			152.9			(320.0		)	167.3
	Less: Net income attributable to noncontrolling	—			—			0.1			—			0.1
	interests
	Net income attributable to ONEOK Partners, L.P.	$	167.2		$	167.2		$	152.8		$	(320.0	)	$	167.2
		Three Months Ended September 30, 2013
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Revenues
	Commodity sales	$	—		$	—		$	2,807.30		$	—		$	2,807.30
	Services	—			—			327.4			—			327.4
	Total revenues	—			—			3,134.70			—			3,134.70
	Cost of sales and fuel	—			—			2,711.10			—			2,711.10
	Net margin	—			—			423.6			—			423.6
	Operating expenses
	Operations and maintenance	—			—			109			—			109
	Depreciation and amortization	—			—			61.2			—			61.2
	General taxes	—			—			13.3			—			13.3
	Total operating expenses	—			—			183.5			—			183.5
	Operating income	—			—			240.1			—			240.1
	Equity earnings from investments	216.3			216.3			11			(416.1		)	27.5
	Allowance for equity funds used during	—			—			6.4			—			6.4
	construction
	Other income (expense), net	70.6			70.6			3.1			(141.2		)	3.1
	Interest expense, net	(70.6		)	(70.6		)	(57.7		)	141.2			(57.7		)
	Income before income taxes	216.3			216.3			202.9			(416.1		)	219.4
	Income taxes	—			—			(3.0		)	—			(3.0		)
	Net income	216.3			216.3			199.9			(416.1		)	216.4
	Less: Net income attributable to noncontrolling	—			—			0.1			—			0.1
interests
Net income attributable to ONEOK Partners, L.P.	$	216.3		$	216.3		$	199.8		$	(416.1	)	$	216.3
	Nine Months Ended September 30, 2014
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Revenues
Commodity sales	$	—		$	—		$	8,276.30		$	—		$	8,276.30
Services	—			—			1,071.10			—			1,071.10
Total revenues	—			—			9,347.40			—			9,347.40
Cost of sales and fuel	—			—			7,807.30			—			7,807.30
Net margin	—			—			1,540.10			—			1,540.10
Operating expenses
Operations and maintenance	—			—			425.6			—			425.6
Depreciation and amortization	—			—			212.1			—			212.1
General taxes	—			—			55.9			—			55.9
Total operating expenses	—			—			693.6			—			693.6
Gain (loss) on sale of assets	—			—			1.5			—			1.5
Operating income	—			—			848			—			848
Equity earnings (loss) from investments	647.1			647.1			(46.9		)	(1,240.6		)	6.7
Allowance for equity funds used during	—			—			13.9			—			13.9
construction
Other income (expense), net	248.9			248.9			—			(497.8		)	—
Interest expense, net	(248.9		)	(248.9		)	(211.3		)	497.8			(211.3		)
Income before income taxes	647.1			647.1			603.7			(1,240.6		)	657.3
Income taxes	—			—			(10.0		)	—			(10.0		)
Net income	647.1			647.1			593.7			(1,240.6		)	647.3
Less: Net income attributable to noncontrolling	—			—			0.2			—			0.2
interests
Net income attributable to ONEOK Partners, L.P.	$	647.1		$	647.1		$	593.5		$	(1,240.6	)	$	647.1
	Nine Months Ended September 30, 2013
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Revenues
Commodity sales	$	—		$	—		$	7,453.50		$	—		$	7,453.50
Services	—			—			966.9			—			966.9
Total revenues	—			—			8,420.40			—			8,420.40
Cost of sales and fuel	—			—			7,214.30			—			7,214.30
Net margin	—			—			1,206.10			—			1,206.10
Operating expenses
Operations and maintenance	—			—			338.4			—			338.4
Depreciation and amortization	—			—			174.1			—			174.1
General taxes	—			—			46.2			—			46.2
Total operating expenses	—			—			558.7			—			558.7
Gain (loss) on sale of assets	—			—			0.4			—			0.4
Operating income	—			—			647.8			—			647.8
Equity earnings from investments	575.3			575.3			31.6			(1,102.5		)	79.7
Allowance for equity funds used during	—			—			21.2			—			21.2
construction
Other income (expense), net	205.1			205.1			5.8			(410.2		)	5.8
Interest expense, net	(205.1		)	(205.1		)	(171.1		)	410.2			(171.1		)
Income before income taxes	575.3			575.3			535.3			(1,102.5		)	583.4
Income taxes	—			—			(7.9		)	—			(7.9		)
Net income	575.3			575.3			527.4			(1,102.5		)	575.5
Less: Net income attributable to noncontrolling	—			—			0.2			—			0.2
interests
Net income attributable to ONEOK Partners, L.P.	$	575.3		$	575.3		$	527.2		$	(1,102.5	)	$	575.3
Condensed Consolidating Statements of Comprehensive Income
	Three Months Ended September 30, 2014
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Net income	$	167.2		$	167.2		$	152.9		$	(320.0	)	$	167.3
Other comprehensive income (loss)
Unrealized gains (losses) on derivatives	7.4			17.1			17.1			(34.2		)	7.4
Realized (gains) losses on derivatives recognized in	3			0.4			0.4			(0.8		)	3
net income
Total other comprehensive income (loss)	10.4			17.5			17.5			(35.0		)	10.4
Comprehensive income	177.6			184.7			170.4			(355.0		)	177.7
Less: Comprehensive income attributable to	—			—			0.1			—			0.1
noncontrolling interests
Comprehensive income attributable to	$	177.6		$	184.7		$	170.3		$	(355.0	)	$	177.6
ONEOK Partners, L.P.
	Three Months Ended September 30, 2013
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Net income	$	216.3		$	216.3		$	199.9		$	(416.1	)	$	216.4
Other comprehensive income (loss)
Unrealized gains (losses) on derivatives	(3.6		)	(10.3		)	(10.3		)	20.6			(3.6		)
Realized (gains) losses on derivatives recognized in	2.2			(0.4		)	(0.4		)	0.8			2.2
net income
Total other comprehensive income (loss)	(1.4		)	(10.7		)	(10.7		)	21.4			(1.4		)
Comprehensive income	214.9			205.6			189.2			(394.7		)	215
Less: Comprehensive income attributable to	—			—			0.1			—			0.1
noncontrolling interests
Comprehensive income attributable to	$	214.9		$	205.6		$	189.1		$	(394.7	)	$	214.9
ONEOK Partners, L.P.
	Nine Months Ended September 30, 2014
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Net income	$	647.1		$	647.1		$	593.7		$	(1,240.6	)	$	647.3
Other comprehensive income (loss)
Unrealized gains (losses) on derivatives	(81.6		)	(24.7		)	(24.7		)	49.4			(81.6		)
Realized (gains) losses on derivatives recognized in	39.8			32			32			(64.0		)	39.8
net income
Total other comprehensive income (loss)	(41.8		)	7.3			7.3			(14.6		)	(41.8		)
Comprehensive income	605.3			654.4			601			(1,255.2		)	605.5
Less: Comprehensive income attributable to	—			—			0.2			—			0.2
noncontrolling interests
Comprehensive income attributable to	$	605.3		$	654.4		$	600.8		$	(1,255.2	)	$	605.3
ONEOK Partners, L.P.
	Nine Months Ended September 30, 2013
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Net income	$	575.3		$	575.3		$	527.4		$	(1,102.5	)	$	575.5
Other comprehensive income (loss)
Unrealized gains (losses) on derivatives	38.8			3.1			3.1			(6.2		)	38.8
Realized (gains) losses on derivatives recognized in	3.2			(4.2		)	(4.2		)	8.4			3.2
net income
Total other comprehensive income (loss)	42			(1.1		)	(1.1		)	2.2			42
Comprehensive income	617.3			574.2			526.3			(1,100.3		)	617.5
Less: Comprehensive income attributable to	—			—			0.2			—			0.2
noncontrolling interests
Comprehensive income attributable to	$	617.3		$	574.2		$	526.1		$	(1,100.3	)	$	617.3
ONEOK Partners, L.P.
Condensed Consolidating Balance Sheets
	September 30, 2014
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
Assets	(Millions of dollars)
Current assets
Cash and cash equivalents	$	—		$	54		$	—		$	—		$	54
Accounts receivable, net	—			—			951.6			—			951.6
Affiliate receivables	—			—			5.9			—			5.9
Natural gas and natural gas liquids in storage	—			—			338.3			—			338.3
Commodity imbalances	—			—			74.3			—			74.3
Other current assets	13.1			—			70.7			—			83.8
Total current assets	13.1			54			1,440.80			—			1,507.90
Property, plant and equipment
Property, plant and equipment	—			—			11,951.50			—			11,951.50
Accumulated depreciation and amortization	—			—			1,837.10			—			1,837.10
Net property, plant and equipment	—			—			10,114.40			—			10,114.40
Investments and other assets
Investments in unconsolidated affiliates	4,222.70			5,179.50			738.9			(9,012.6		)	1,128.50
Intercompany notes receivable	7,612.00			6,601.20			—			(14,213.2		)	—
Goodwill and intangible assets	—			—			825.3			—			825.3
Other assets	56			—			22.1			—			78.1
Total investments and other assets	11,890.70			11,780.70			1,586.30			(23,225.8		)	2,031.90
Total assets	$	11,903.80		$	11,834.70		$	13,141.50		$	(23,225.8	)	$	13,654.20
Liabilities and equity
Current liabilities
Current maturities of long-term debt	$	—		$	—		$	7.7		$	—		$	7.7
Accounts payable	—			—			1,216.10			—			1,216.10
Affiliate payables	—			—			29.4			—			29.4
Commodity imbalances	—			—			171.2			—			171.2
Accrued interest	88			—			—			—			88
Other current liabilities	23.3			—			136			—			159.3
Total current liabilities	111.3			—			1,560.40			—			1,671.70
Intercompany debt	—			7,612.00			6,601.20			(14,213.2		)	—
Long-term debt, excluding current maturities	5,986.20			—			53.8			—			6,040.00
Deferred credits and other liabilities	—			—			131.8			—			131.8
Commitments and contingencies
Equity
Equity excluding noncontrolling interests in	5,806.30			4,222.70			4,789.90			(9,012.6		)	5,806.30
consolidated subsidiaries
Noncontrolling interests in consolidated	—			—			4.4			—			4.4
subsidiaries
Total equity	5,806.30			4,222.70			4,794.30			(9,012.6		)	5,810.70
Total liabilities and equity	$	11,903.80		$	11,834.70		$	13,141.50		$	(23,225.8	)	$	13,654.20
	December 31, 2013
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
Assets	(Millions of dollars)
Current assets
Cash and cash equivalents	$	—		$	134.5		$	—		$	—		$	134.5
Accounts receivable, net	—			—			1,103.10			—			1,103.10
Affiliate receivables	—			—			9.2			—			9.2
Natural gas and natural gas liquids in storage	—			—			188.3			—			188.3
Commodity imbalances	—			—			80.5			—			80.5
Other current assets	4.8			—			62.7			—			67.5
Total current assets	4.8			134.5			1,443.80			—			1,583.10
Property, plant and equipment
Property, plant and equipment	—			—			10,755.00			—			10,755.00
Accumulated depreciation and amortization	—			—			1,652.60			—			1,652.60
Net property, plant and equipment	—			—			9,102.40			—			9,102.40
Investments and other assets
Investments in unconsolidated affiliates	4,336.40			4,593.10			825.6			(8,525.3		)	1,229.80
Intercompany notes receivable	6,638.30			6,247.10			—			(12,885.4		)	—
Goodwill and intangible assets	—			—			832.2			—			832.2
Other assets	92.7			—			22.4			—			115.1
Total investments and other assets	11,067.40			10,840.20			1,680.20			(21,410.7		)	2,177.10
Total assets	$	11,072.20		$	10,974.70		$	12,226.40		$	(21,410.7	)	$	12,862.60
Liabilities and equity
Current liabilities
Current maturities of long-term debt	$	—		$	—		$	7.7		$	—		$	7.7
Accounts payable	—			—			1,255.40			—			1,255.40
Affiliate payables	—			—			47.5			—			47.5
Commodity imbalances	—			—			213.6			—			213.6
Accrued interest	92.7			—			—			—			92.7
Other current liabilities	—			—			89.1			—			89.1
Total current liabilities	92.7			—			1,613.30			—			1,706.00
Intercompany debt	—			6,638.30			6,247.10			(12,885.4		)	—
Long-term debt, excluding current maturities	5,985.30			—			59.6			—			6,044.90
Deferred credits and other liabilities	—			—			113			—			113
Commitments and contingencies
Equity
Equity excluding noncontrolling interests in	4,994.20			4,336.40			4,188.90			(8,525.3		)	4,994.20
consolidated subsidiaries
Noncontrolling interests in consolidated	—			—			4.5			—			4.5
subsidiaries
Total equity	4,994.20			4,336.40			4,193.40			(8,525.3		)	4,998.70
Total liabilities and equity	$	11,072.20		$	10,974.70		$	12,226.40		$	(21,410.7	)	$	12,862.60
Condensed Consolidating Statements of Cash Flows
	Nine Months Ended September 30, 2014
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Operating activities
Cash provided by operating activities	$	815.1		$	53.7		$	786.4		$	(768.1	)	$	887.1
Investing activities
Capital expenditures (less allowance for equity	—			—			(1,173.0		)	—			(1,173.0		)
funds used during construction)
Acquisition	—			—			(14.0		)	—			(14.0		)
Contributions to unconsolidated affiliates	—			—			(1.0		)	—			(1.0		)
Distributions received from unconsolidated	—			14.5			10.4			—			24.9
affiliates
Proceeds from sale of assets	—			—			2.4			—			2.4
Cash provided by (used in) investing activities	—			14.5			(1,175.2		)	—			(1,160.7		)
Financing activities
Cash distributions:
General and limited partners	(768.1		)	(768.1		)	—			768.1			(768.1		)
Noncontrolling interests	—			—			(0.4		)	—			(0.4		)
Borrowing of notes payable, net	—			—			—			—			—
Intercompany borrowings (advances), net	(1,014.3		)	619.4			394.9			—			—
Repayment of long-term debt	—			—			(5.7		)	—			(5.7		)
Issuance of common units, net of issuance costs	947.5			—			—			—			947.5
Contribution from general partner	19.8			—			—			—			19.8
Cash provided by (used in) financing activities	(815.1		)	(148.7		)	388.8			768.1			193.1
Change in cash and cash equivalents	—			(80.5		)	—			—			(80.5		)
Cash and cash equivalents at beginning of	—			134.5			—			—			134.5
period
Cash and cash equivalents at end of period	$	—		$	54		$	—		$	—		$	54
	Nine Months Ended September 30, 2013
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Operating activities
Cash provided by operating activities	$	641.5		$	48.1		$	634.5		$	(670.0	)	$	654.1
Investing activities
Capital expenditures (less allowance for equity	—			—			(1,373.9		)	—			(1,373.9		)
funds used during construction)
Acquisition	—			—			(304.9		)	—			(304.9		)
Contributions to unconsolidated affiliates	—			—			(4.6		)	—			(4.6		)
Distributions received from unconsolidated	—			17.3			7.6			—			24.9
affiliates
Proceeds from sale of assets	—			—			0.7			—			0.7
Cash provided by (used in) investing activities	—			17.3			(1,675.1		)	—			(1,657.8		)
Financing activities
Cash distributions:
General and limited partners	(670.0		)	(670.0		)	—			670			(670.0		)
Noncontrolling interests	—			—			(0.4		)	—			(0.4		)
Borrowings of notes payable, net	47			—			—			—			47
Issuance of long-term debt, net of discounts	1,247.80			—			—			—			1,247.80
Long-term debt financing costs	(10.2		)	—			—			—			(10.2		)
Intercompany borrowings (advances), net	(1,837.2		)	790.5			1,046.70			—			—
Repayment of long-term debt	—			—			(5.7		)	—			(5.7		)
Issuance of common units, net of issuance costs	569.2			—			—			—			569.2
Contribution from general partner	11.9			—			—			—			11.9
Cash provided by (used in) financing activities	(641.5		)	120.5			1,040.60			670			1,189.60
Change in cash and cash equivalents	—			185.9			—			—			185.9
Cash and cash equivalents at beginning of	—			537.1			—			—			537.1
period
Cash and cash equivalents at end of period	$	—		$	723		$	—		$	—		$	723

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 30, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'
Basis of Accounting, Policy [Policy Text Block]	'
	Our accompanying unaudited consolidated financial statements have been prepared pursuant to the rules and regulations of the SEC. These statements have been prepared in accordance with GAAP and reflect all adjustments that, in our opinion, are necessary for a fair presentation of the results for the interim periods presented.  All such adjustments are of a normal recurring nature. The 2013 year-end consolidated balance sheet data was derived from our audited financial statements but does not include all disclosures required by GAAP.  These unaudited consolidated financial statements should be read in conjunction with our audited consolidated financial statements in our Annual Report.
	Our significant accounting policies are consistent with those disclosed in Note A of the Notes to Consolidated Financial Statements in our Annual Report.
Accounting Standards Update 2014-08 [Member]	'
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	'Recently Issued Accounting Standards Update - In April 2014, the FASB issued ASU 2014-08, bReporting Discontinued Operations and Disclosures of Disposals of Components of an Entity,b which alters the definition of a discontinued operation to include only asset disposals that represent a strategic shift with a major effect on an entity's operations and financial results.B The amendments also require more extensive disclosures about a discontinued operation's assets, liabilities, income, expenses and cash flows. This guidance will be effective for interim and annual periods for all assets that are disposed of, or classified as being held for sale, in fiscal years that begin on or after December 15, 2014. We will adopt this guidance beginning in the first quarter 2015, and it could impact us in the future if we dispose of any individually significant components.
Accounting Standards Update 2014-09 [Member]	'
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	'In May 2014, the FASB issued ASU 2014-09, bRevenue from Contracts with Customers,b which outlines the principles an entity must apply to measure and recognize revenue for entities that enter into contracts to provide goods or services to their customers. The core principle is that an entity should recognize revenue at an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring goods or services to a customer. The amendments also require more extensive disaggregated revenue disclosures in interim and annual financial statements. This update will be effective for interim and annual periods that begin on or after December 15, 2016, with either retrospective application for all periods presented or retrospective application with a cumulative effect adjustment. We will adopt this guidance beginning in the first quarter 2017, and we are evaluating the impact on us.
Accounting Standards Update 2014-15 [Domain]	'
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'
New Accounting Pronouncement or Change in Accounting Principle, Description	'In August 2014, the FASB issued ASU 2014-15, bGoing Concern,b which provides guidance on determining when and how to disclose going-concern uncertainties in the financial statements. The new standard requires management to perform interim and annual assessments of an entitybs ability to continue as a going concern within one year of the date the financial statements are issued. An entity must provide certain disclosures if conditions or events raise substantial doubt about the entitybs ability to continue as a going concern. The standard applies to all entities and is effective for annual periods ending after December 15, 2016, and interim periods thereafter, with early adoption permitted. We will adopt this guidance beginning in the first quarter 2017, and we do not expect it to materially impact us.

ACQUISITIONS_ACQUISITIONS_Poli

ACQUISITIONS ACQUISITIONS (Policies)	9 Months Ended
	Sep. 30, 2014
Business Acquisition [Line Items]	'
Business Combinations Policy [Policy Text Block]	'
	We 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.

FAIR_VALUE_MEASUREMENTS_Determ

FAIR VALUE MEASUREMENTS Determining Fair Value (Policies)	9 Months Ended
	Sep. 30, 2014
Fair Value Accounting Policy [Abstract]	'
Fair Value of Financial Instruments, Policy [Policy Text Block]	'
	Determining Fair Value - 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 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 groups 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.  For certain transactions, we utilize modeling techniques using NYMEX-settled pricing data and implied forward LIBOR curves.  Inputs into our fair value estimates include commodity-exchange prices, over-the-counter quotes, 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 monitoring 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 are 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 - fair value measurements are based on unadjusted quoted prices in active markets including NYMEX-settled prices. These balances are comprised predominantly of exchange-traded derivative contracts for natural gas and crude oil.
	•	Level 2 - fair value measurements 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.
	•	Level 3 - fair value measurements 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. 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.
Investment, Policy [Policy Text Block]	'
	During the three months ended September 30, 2014, we recorded a noncash impairment to our equity investment in Bighorn Gas Gathering. The valuation of this investment required use of significant unobservable inputs. We used an income approach to estimate the fair value of our investment. Our discounted cash flow analysis included the following inputs that are not readily available: a discount rate reflective of our cost of capital and estimated contract rates, volumes, operating and maintenance costs and capital expenditures. The estimated fair value of this investment is classified as Level 3.

RISK_MANAGEMENT_AND_HEDGING_AC1

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES (Policies)	9 Months Ended
	Sep. 30, 2014
RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES [Abstract]	'
Accounting treatment for derivative instruments	'
	Accounting Treatment - 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.
	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 normal sales	-	Fair value not recorded	-	Change in fair value not recognized in earnings
	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		derivative instrument is reclassified out of
			as a 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
	Under certain conditions, we designate our derivative instruments as a hedge of exposure to changes in fair values or cash flows. 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 forecasted transaction that has been designated as the hedged item in a cash flow hedge relationship.  We assess the effectiveness of hedging relationships quarterly by performing an effectiveness analysis on our fair value and cash flow 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 realized revenues and purchase costs of our derivative instruments not considered held for trading purposes and derivatives that qualify as normal purchases or normal sales that are expected to result in physical delivery are reported on a gross basis.
	Cash flows from futures, forwards 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.

EQUITY_Policies

EQUITY (Policies)	9 Months Ended
	Sep. 30, 2014
EQUITY (Policies)	'
Partnership agreement	'
	Partnership Agreement - Available cash, as defined in our Partnership Agreement, generally will be distributed to our general partner and limited partners according to their partnership percentages of 2 percent and 98 percent, respectively. Our general partner’s percentage interest in quarterly distributions is increased after certain specified target levels are met during the quarter. Under the incentive distribution provisions, as set forth in our Partnership Agreement, our 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.

RELATEDPARTY_TRANSACTIONS_Allo

RELATED-PARTY TRANSACTIONS Allocation of Costs Incurred by Related Party (Policies)	9 Months Ended
	Sep. 30, 2014
Related Party Transactions [Abstract]	'
Allocation of Costs Incurred by Related Party, Policy [Policy Text Block]	'
	ONEOK and its affiliates provide a variety of services to us under the Services Agreement, including cash management and financial services, employee benefits provided through ONEOK’s benefit plans, legal and administrative services, insurance and office space leased in ONEOK’s headquarters building and other field locations.  Where costs are incurred specifically on behalf of one of our affiliates, the costs are billed directly to us by ONEOK.  In other situations, the costs may be allocated to us through a variety of methods, depending upon the nature of the expense and activities. Beginning in the second quarter 2014, ONEOK allocates substantially all of its general overhead costs to us as a result of ONEOK’s separation of its natural gas distribution business and the wind down of its energy services business in the first quarter 2014.  For the first quarter 2014 and the three and nine months ended September 30, 2013, it is not practicable to determine what these general overhead costs would have been on a stand-alone basis.  All costs directly charged or allocated to us are included in our Consolidated Statements of Income.

SEGMENTS_Policies

SEGMENTS (Policies)	9 Months Ended
	Sep. 30, 2014
Segment Accounting Policies [Abstract]	'
Segment Reporting, Policy [Policy Text Block]	'
	Accounting Policies - We evaluate performance based principally on each segment’s operating income and equity earnings. The accounting policies of the segments are described in Note A of the Notes to Consolidated Financial Statements in our Annual Report. Affiliate and intersegment sales are recorded on the same basis as sales to unaffiliated customers.  Net margin is comprised of total revenues less cost of sales and fuel.  Cost of sales and fuel includes commodity purchases, fuel, storage and transportation costs.
	As a result of ONEOK’s separation of its natural gas distribution business into a stand-alone publicly traded company called ONE Gas on January 31, 2014, transactions with ONE Gas subsequent to the separation are reflected as sales to unaffiliated customers.

ACQUISITIONS_ACQUISITIONS_Tabl

ACQUISITIONS ACQUISITIONS (Tables)	9 Months Ended
	Sep. 30, 2014
Acquired Finite-Lived Intangible Assets [Line Items]	'
Business Combinations Policy [Policy Text Block]	'
	We 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.

FAIR_VALUE_MEASUREMENTS_Tables

FAIR VALUE MEASUREMENTS (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Recurring Fair Value Measurements	'
	Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements for the periods indicated:
		September 30, 2014
		Level 1			Level 2			Level 3			Total - Gross			Netting (a)			Total - Net (b)
		(Thousands of dollars)
	Derivatives assets
	Commodity contracts
	Financial contracts	$	9,093		$	439		$	—		$	9,532		$	(3,004	)	$	6,528
	Physical contracts	—			—			2,900			2,900			(329		)	2,571
	Interest-rate contracts	—			20,962			—			20,962			—			20,962
	Total derivative assets	$	9,093		$	21,401		$	2,900		$	33,394		$	(3,333	)	$	30,061
	Derivatives liabilities
	Commodity contracts
	Financial contracts	$	(83	)	$	—		$	(2,921	)	$	(3,004	)	$	3,004		$	—
	Physical contracts	—			—			(683		)	(683		)	329			(354		)
	Interest-rate contracts	—			(23,308		)	—			(23,308		)	—			(23,308		)
	Total derivative liabilities	$	(83	)	$	(23,308	)	$	(3,604	)	$	(26,995	)	$	3,333		$	(23,662	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis.  We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At September 30, 2014, we had no cash collateral held or posted.
	(b) - Included in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.
		December 31, 2013
		Level 1			Level 2			Level 3			Total - Gross			Netting (a)			Total - Net (b)
		(Thousands of dollars)
	Derivatives assets
	Commodity contracts
	Financial contracts	$	—		$	3,657		$	2,812		$	6,469		$	(1,746	)	$	4,723
	Physical contracts	—			—			2,023			2,023			(946		)	1,077
	Interest-rate contracts	—			54,503			—			54,503			—			54,503
	Total derivative assets	$	—		$	58,160		$	4,835		$	62,995		$	(2,692	)	$	60,303
	Derivatives liabilities
	Commodity contracts
	Financial contracts	$	—		$	(2,953	)	$	(2,154	)	$	(5,107	)	$	1,746		$	(3,361	)
	Physical contracts	—			—			(3,463		)	(3,463		)	946			(2,517		)
	Total derivative liabilities	$	—		$	(2,953	)	$	(5,617	)	$	(8,570	)	$	2,692		$	(5,878	)
	(a) - Our derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis.  We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2013, we had no cash collateral held or posted.
	(b) - Included in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.
Reconciliation of Level 3 Fair Value Measurements	'
	The following table sets forth a reconciliation of our Level 3 fair value measurements for the periods indicated:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	Derivative Assets (Liabilities)	2014			2013			2014			2013
		(Thousands of dollars)
	Net assets (liabilities) at beginning of period	$	(1,313	)	$	7,682		$	(782	)	$	(2,423	)
	Total realized/unrealized gains (losses):
	Included in earnings (a)	207			—			(688		)	—
	Included in other comprehensive income (loss)	402			(7,181		)	(2,968		)	2,924
	Purchases, issuances and settlements	—			—			3,734			—
	Net assets (liabilities) at end of period	$	(704	)	$	501		$	(704	)	$	501
	(a) - Included in commodity sales revenues in our Consolidated Statements of Income.

RISK_MANAGEMENT_AND_HEDGING_AC2

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES (Tables)	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Schedule of Derivative Instruments in Statement of Financial Position	'
	Fair Values of Derivative Instruments - See Note C for a discussion of the inputs associated with our fair value measurements. The following table sets forth the fair values of our derivative instruments:
		September 30, 2014								December 31, 2013
		Assets (a)				(Liabilities) (a)				Assets (a)				(Liabilities) (a)
		(Thousands of dollars)
	Derivatives designated as hedging instruments
	Commodity contracts
	Financial contracts	$	9,532			$	(3,004	)		$	6,469			$	(5,107	)
	Physical contracts	2,554				(608		)		1,064				(3,463		)
	Interest-rate contracts	20,962				(23,308		)		54,503				—
	Total derivatives designated as hedging instruments	$	33,048			$	(26,920	)		$	62,036			$	(8,570	)
	Derivatives not designated as hedging instruments
	Commodity contracts
	Physical contracts	346				(75		)		959				—
	Total derivatives not designated as hedging instruments	346				(75		)		959				—
	Total derivatives	$	33,394			$	(26,995	)		$	62,995			$	(8,570	)
	(a) - Included on a net basis in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.
Schedule of Notional Quantities for Derivative Instruments	'
	Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for derivative instruments designated as hedging instruments for the periods indicated:
			30-Sep-14								December 31, 2013
		Contract	Purchased/				Sold/				Purchased/				Sold/
		Type	Payor				Receiver				Payor				Receiver
	Derivatives designated as hedging instruments:
	Cash flow hedges
	Fixed price
	- Natural gas (Bcf)	Futures and swaps	—				(31.2		)		—				(48.1		)
	- Crude oil and NGLs (MMBbl)	Futures, forwards	—				(1.7		)		—				(4.0		)
		and swaps
	Basis
	- Natural gas (Bcf)	Futures and swaps	—				(31.2		)		—				(48.1		)
	Interest-rate contracts (Millions of dollars)	Forward-starting	$	900			$	—			$	400			$	—
		swaps
Schedule of Cash Flow Hedges in Other Comprehensive Income (Loss)	'
	The following table sets forth the effect of cash flow hedges recognized in other comprehensive income (loss) for the periods indicated:
		Three Months Ended								Nine Months Ended
	Derivatives in Cash Flow	September 30,								September 30,
	Hedging Relationships	2014				2013				2014				2013
		(Thousands of dollars)
	Commodity contracts	$	17,133			$	(10,317	)		$	(24,743	)		$	3,060
	Interest-rate contracts	(9,755		)		6,721				(56,849		)		35,726
	Total unrealized gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion)	$	7,378			$	(3,596	)		$	(81,592	)		$	38,786
Schedule of Derivative Instruments, Gain (loss) of Statement of Financial Performance	'
	The following table sets forth the effect of cash flow hedges in our Consolidated Statements of Income for the periods indicated:
	Derivatives in Cash Flow	Location of Gain (Loss) Reclassified from	Three Months Ended								Nine Months Ended
	Hedging Relationships	Accumulated Other Comprehensive Income	September 30,								September 30,
		(Loss) into Net Income (Effective Portion)	2014				2013				2014				2013
			(Thousands of dollars)
	Commodity contracts	Commodity sales revenues	$	(355	)		$	361			$	(31,961	)		$	4,172
	Interest-rate contracts	Interest expense	(2,648		)		(2,565		)		(7,884		)		(7,445		)
	Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income on derivatives (effective portion)		$	(3,003	)		$	(2,204	)		$	(39,845	)		$	(3,273	)

EQUITY_Tables

EQUITY (Tables)	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Schedule of distributions made to general or limited partner	'
	The following table shows our distributions paid in the periods indicated:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2014		2013		2014		2013
		(Thousands, except per unit amounts)
	Distribution per unit	$	0.76	$	0.72	$	2.235	$	2.145
	General partner distributions	$	5,501	$	4,512	$	15,361	$	13,399
	Incentive distributions	80,381		62,634		220,547		184,647
	Distributions to general partner	85,882		67,146		235,908		198,046
	Limited partner distributions to ONEOK	70,519		66,807		207,381		199,031
	Limited partner distributions to other unitholders	118,644		91,676		324,805		272,904
	Total distributions paid	$	275,045	$	225,629	$	768,094	$	669,981
Schedule of distributions declared to general or limited partner	'
	The following table shows our distributions declared for the periods indicated and paid within 45 days of the end of the period:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2014		2013		2014		2013
		(Thousands, except per unit amounts)
	Distribution per unit	$	0.775	$	0.725	$	2.28	$	2.16
	General partner distributions	$	5,683	$	4,795	$	16,195	$	13,776
	Incentive distributions	84,452		67,017		236,744		191,226
	Distributions to general partner	90,135		71,812		252,939		205,002
	Limited partner distributions to ONEOK	71,911		67,271		211,557		200,422
	Limited partner distributions to other unitholders	122,105		100,650		345,255		283,365
	Total distributions declared	$	284,151	$	239,733	$	809,751	$	688,789

ACCUMULATED_OTHER_COMPREHENSIV1

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) ACCUMULATED OTHER COMPREHENSIVE INCOME (Tables)	9 Months Ended
	Sep. 30, 2014
Accumulated other comprehensive income (loss)	'
	The following table sets forth the balance in accumulated other comprehensive income (loss) for the period indicated:
		Accumulated
		Other
		Comprehensive
		Loss (a)
		(Thousands of dollars)
	1-Jan-14	$	(58,837	)
	Other comprehensive income (loss) before classifications	(81,592		)
	Amounts reclassified from accumulated other comprehensive income (loss)	39,845
	Net current-period other comprehensive income (loss) attributable to ONEOK Partners	(41,747		)
	September 30, 2014	$	(100,584	)
	(a) All amounts are attributable to unrealized gains (losses) in risk-management assets/liabilities.
Disclosure of Reclassification Amount [Text Block]	'
	The following table sets forth the effect of reclassifications from accumulated other comprehensive income (loss) in our Consolidated Statements of Income for the periods indicated:
	Details about Accumulated Other	Three Months Ended						Nine Months Ended					Affected Line Item in the
	Comprehensive Income (Loss) Components	September 30,						September 30,					Consolidated Statements of Income
		2014			2013			2014		2013
		(Thousands of dollars)
	Unrealized (gains) losses on risk-management assets/liabilities
	Commodity contracts	$	355		$	(361	)	$	31,961	$	(4,172	)	Commodity sales revenues
	Interest-rate contracts	2,648			2,565			7,884		7,445			Interest expense
	Total reclassifications for the period attributable to ONEOK Partners	$	3,003		$	2,204		$	39,845	$	3,273		Net income attributable to ONEOK Partners

UNCONSOLIDATED_AFFILIATES_Tabl

UNCONSOLIDATED AFFILIATES (Tables)	9 Months Ended
	Sep. 30, 2014
Equity Method Investments and Joint Ventures [Abstract]	'
Unconsolidated Affiliates Financial Information	'
	Equity Earnings from Investments - The following table sets forth our equity earnings (losses) from investments for the periods indicated:
		Three Months Ended					Nine Months Ended
		September 30,					September 30,
		2014			2013		2014			2013
		(Thousands of dollars)
	Share of investee earnings (loss)
	Northern Border Pipeline	$	14,371		$	16,464	$	53,657		$	48,133
	Overland Pass Pipeline Company	3,856			5,783		12,708			14,210
	Fort Union Gas Gathering	4,169			2,946		12,578			9,895
	Bighorn Gas Gathering (a)	(23,472		)	559		(24,745		)	1,897
	Other	2,150			1,716		5,970			5,609
	Total share of investee earnings	1,074			27,468		60,168			79,744
	Impairment of investment in Bighorn Gas Gathering	(53,421		)	—		(53,421		)	—
	Equity earnings (loss) from investments	$	(52,347	)	$	27,468	$	6,747		$	79,744
	(a) Includes proportionate share of investee impairment of long-lived assets charge of $23.0 million.
Unconsolidated Affiliates Financial Information [Table Text Block]	'
	Unconsolidated Affiliates Financial Information - The following table sets forth summarized combined financial information of our unconsolidated affiliates for the periods indicated:
		Three Months Ended					Nine Months Ended
		September 30,					September 30,
		2014			2013		2014			2013
		(Thousands of dollars)
	Income Statement
	Operating revenues	$	126,218		$	131,959	$	403,006		$	391,912
	Operating expenses (a)	$	123,620		$	63,971	$	247,169		$	189,366
	Net income (loss) (a)	$	(5,119	)	$	61,630	$	134,432		$	185,580
	Distributions paid to us	$	31,574		$	34,409	$	109,223		$	103,913
	(a) - Includes long-lived asset impairment charge on Bighorn Gas Gathering.

RELATEDPARTY_TRANSACTIONS_Tabl

RELATED-PARTY TRANSACTIONS (Tables)	9 Months Ended
	Sep. 30, 2014
Related Party Transactions [Abstract]	'
Schedule of Related Party Transactions [Table Text Block]	'
	The following table sets forth the transactions with related parties for the periods indicated:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2014		2013		2014		2013
		(Thousands of dollars)
	Revenues	$	—	$	81,324	$	53,526	$	255,298
	Expenses
	Cost of sales and fuel	$	—	$	9,562	$	10,835	$	27,855
	Administrative and general expenses	84,221		58,549		240,172		192,906
	Total expenses	$	84,221	$	68,111	$	251,007	$	220,761

SEGMENTS_Tables

SEGMENTS (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]	'
Selected Financial Information by Reportable Segment	'
	Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated:
	Three Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-14	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	374,403		$	2,667,939		$	77,027		$	—		$	3,119,369
	Intersegment revenues	403,399			66,581			2,133			(472,113		)	—
	Total revenues	$	777,802		$	2,734,520		$	79,160		$	(472,113	)	$	3,119,369
	Net margin	$	178,171		$	282,963		$	73,399		$	1,632		$	536,165
	Operating costs	64,279			76,946			27,998			1,562			170,785
	Depreciation and amortization	31,327			31,661			10,913			—			73,901
	Gain (loss) on sale of assets	324			(535		)	1,746			(1		)	1,534
	Operating income	$	82,889		$	173,821		$	36,234		$	69		$	293,013
	Equity earnings (loss) from investments	$	(71,069	)	$	4,351		$	14,371		$	—		$	(52,347	)
	Capital expenditures	$	214,917		$	153,785		$	10,650		$	1,184		$	380,536
	(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $190.3 million, of which $170.1 million was related to sales within the segment, net margin of $94.3 million and operating income of $46.4 million.
	(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $65.2 million, net margin of $57.4 million and operating income of $23.4 million.
	Three Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-13	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	162,677		$	2,840,108		$	50,624		$	—		$	3,053,409
	Sales to affiliated customers	57,400			—			23,924			—			81,324
	Intersegment revenues	312,940			34,740			1,330			(349,010		)	—
	Total revenues	$	533,017		$	2,874,848		$	75,878		$	(349,010	)	$	3,134,733
	Net margin	$	130,882		$	226,242		$	69,457		$	(3,007	)	$	423,574
	Operating costs	45,074			57,010			23,457			(3,179		)	122,362
	Depreciation and amortization	27,356			22,993			10,833			—			61,182
	Gain (loss) on sale of assets	31			7			(16		)	—			22
	Operating income	$	58,483		$	146,246		$	35,151		$	172		$	240,052
	Equity earnings from investments	$	4,668		$	6,336		$	16,464		$	—		$	27,468
	Capital expenditures	$	204,542		$	230,780		$	11,148		$	2,602		$	449,072
	(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $147.1 million, of which $130.2 million was related to sales within the segment, net margin of $89.5 million and operating income of $53.4 million.
	(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $57.5 million, net margin of $52.8 million and operating income of $22.6 million.
	Nine Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-14	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	1,095,531		$	7,950,930		$	247,420		$	—		$	9,293,881
	Sales to affiliated customers	41,214			—			12,312			—			53,526
	Intersegment revenues	1,126,547			160,712			6,206			(1,293,465		)	—
	Total revenues	$	2,263,292		$	8,111,642		$	265,938		$	(1,293,465	)	$	9,347,407
	Net margin	$	486,695		$	818,086		$	242,359		$	(7,008	)	$	1,540,132
	Operating costs	188,489			218,129			82,747			(7,752		)	481,613
	Depreciation and amortization	89,612			89,848			32,623			—			212,083
	Gain (loss) on sale of assets	277			(572		)	1,663			165			1,533
	Operating income	$	208,871		$	509,537		$	128,652		$	909		$	847,969
	Equity earnings (loss) from investments	$	(60,484	)	$	13,574		$	53,657		$	—		$	6,747
	Investments in unconsolidated affiliates	$	253,930		$	484,238		$	390,341		$	—		$	1,128,509
	Total assets	$	4,415,814		$	7,337,688		$	1,832,368		$	68,372		$	13,654,242
	Noncontrolling interests in consolidated subsidiaries	$	4,394		$	—		$	—		$	15		$	4,409
	Capital expenditures	$	506,016		$	637,524		$	25,987		$	3,423		$	1,172,950
	(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $479.4 million, of which $417.0 million was related to sales within the segment, net margin of $263.4 million and operating income of $126.0 million.
	(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $214.8 million, net margin of $185.5 million and operating income of $84.6 million.
	Nine Months Ended	Natural Gas			Natural Gas			Natural Gas			Other and			Total
		Gathering and			Liquids (a)			Pipelines (b)			Eliminations
	30-Sep-13	Processing
		(Thousands of dollars)
	Sales to unaffiliated customers	$	466,631		$	7,539,470		$	158,960		$	—		$	8,165,061
	Sales to affiliated customers	179,636			—			75,662			—			255,298
	Intersegment revenues	806,523			91,161			2,327			(900,011		)	—
	Total revenues	$	1,452,790		$	7,630,631		$	236,949		$	(900,011	)	$	8,420,359
	Net margin	$	365,436		$	632,087		$	211,224		$	(2,621	)	$	1,206,126
Operating costs	141,737			171,076			75,608			(3,819		)	384,602
Depreciation and amortization	76,366			65,033			32,687			—			174,086
Gain (loss) on sale of assets	344			10			(12		)	—			342
Operating income	$	147,677		$	395,988		$	102,917		$	1,198		$	647,780
Equity earnings from investments	$	16,228		$	15,383		$	48,133		$	—		$	79,744
Investments in unconsolidated affiliates	$	331,124		$	494,702		$	376,047		$	—		$	1,201,873
Total assets	$	3,808,135		$	6,610,205		$	1,786,413		$	658,573		$	12,863,326
Noncontrolling interests in consolidated subsidiaries	$	4,574		$	—		$	—		$	14		$	4,588
Capital expenditures	$	574,509		$	774,284		$	22,497		$	2,614		$	1,373,904
(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $376.9 million, of which $321.3 million was related to sales within the segment, net margin of $227.8 million and operating income of $129.0 million.
(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $182.0 million, net margin of $162.5 million and operating income of $67.0 million.

SUPPLEMENTAL_CONDENSED_CONSOLI1

SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]	'
Condensed Consolidating Statements of Income	'
	Condensed Consolidating Statements of Income
		Three Months Ended September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Revenues
	Commodity sales	$	—		$	—		$	2,754.50		$	—		$	2,754.50
	Services	—			—			364.9			—			364.9
	Total revenues	—			—			3,119.40			—			3,119.40
	Cost of sales and fuel	—			—			2,583.20			—			2,583.20
	Net margin	—			—			536.2			—			536.2
	Operating expenses
	Operations and maintenance	—			—			152.5			—			152.5
	Depreciation and amortization	—			—			73.9			—			73.9
	General taxes	—			—			18.3			—			18.3
	Total operating expenses	—			—			244.7			—			244.7
	Gain (loss) on sale of assets	—			—			1.5			—			1.5
	Operating income	—			—			293			—			293
	Equity earnings (loss) from investments	167.2			167.2			(66.7		)	(320.0		)	(52.3		)
	Allowance for equity funds used during	—			—			1.7			—			1.7
	construction
	Other income (expense), net	83.1			83.1			(2.4		)	(166.2		)	(2.4		)
	Interest expense, net	(83.1		)	(83.1		)	(70.1		)	166.2			(70.1		)
	Income before income taxes	167.2			167.2			155.5			(320.0		)	169.9
	Income taxes	—			—			(2.6		)	—			(2.6		)
	Net income	167.2			167.2			152.9			(320.0		)	167.3
	Less: Net income attributable to noncontrolling	—			—			0.1			—			0.1
	interests
	Net income attributable to ONEOK Partners, L.P.	$	167.2		$	167.2		$	152.8		$	(320.0	)	$	167.2
		Three Months Ended September 30, 2013
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Revenues
	Commodity sales	$	—		$	—		$	2,807.30		$	—		$	2,807.30
	Services	—			—			327.4			—			327.4
	Total revenues	—			—			3,134.70			—			3,134.70
	Cost of sales and fuel	—			—			2,711.10			—			2,711.10
	Net margin	—			—			423.6			—			423.6
	Operating expenses
	Operations and maintenance	—			—			109			—			109
	Depreciation and amortization	—			—			61.2			—			61.2
	General taxes	—			—			13.3			—			13.3
	Total operating expenses	—			—			183.5			—			183.5
	Operating income	—			—			240.1			—			240.1
	Equity earnings from investments	216.3			216.3			11			(416.1		)	27.5
	Allowance for equity funds used during	—			—			6.4			—			6.4
	construction
	Other income (expense), net	70.6			70.6			3.1			(141.2		)	3.1
	Interest expense, net	(70.6		)	(70.6		)	(57.7		)	141.2			(57.7		)
	Income before income taxes	216.3			216.3			202.9			(416.1		)	219.4
	Income taxes	—			—			(3.0		)	—			(3.0		)
	Net income	216.3			216.3			199.9			(416.1		)	216.4
	Less: Net income attributable to noncontrolling	—			—			0.1			—			0.1
	interests
	Net income attributable to ONEOK Partners, L.P.	$	216.3		$	216.3		$	199.8		$	(416.1	)	$	216.3
		Nine Months Ended September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
Revenues
Commodity sales	$	—		$	—		$	8,276.30		$	—		$	8,276.30
Services	—			—			1,071.10			—			1,071.10
Total revenues	—			—			9,347.40			—			9,347.40
Cost of sales and fuel	—			—			7,807.30			—			7,807.30
Net margin	—			—			1,540.10			—			1,540.10
Operating expenses
Operations and maintenance	—			—			425.6			—			425.6
Depreciation and amortization	—			—			212.1			—			212.1
General taxes	—			—			55.9			—			55.9
Total operating expenses	—			—			693.6			—			693.6
Gain (loss) on sale of assets	—			—			1.5			—			1.5
Operating income	—			—			848			—			848
Equity earnings (loss) from investments	647.1			647.1			(46.9		)	(1,240.6		)	6.7
Allowance for equity funds used during	—			—			13.9			—			13.9
construction
Other income (expense), net	248.9			248.9			—			(497.8		)	—
Interest expense, net	(248.9		)	(248.9		)	(211.3		)	497.8			(211.3		)
Income before income taxes	647.1			647.1			603.7			(1,240.6		)	657.3
Income taxes	—			—			(10.0		)	—			(10.0		)
Net income	647.1			647.1			593.7			(1,240.6		)	647.3
Less: Net income attributable to noncontrolling	—			—			0.2			—			0.2
interests
Net income attributable to ONEOK Partners, L.P.	$	647.1		$	647.1		$	593.5		$	(1,240.6	)	$	647.1
	Nine Months Ended September 30, 2013
(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
				Subsidiary			Non-Guarantor			Entries
							Subsidiaries
	(Millions of dollars)
Revenues
Commodity sales	$	—		$	—		$	7,453.50		$	—		$	7,453.50
Services	—			—			966.9			—			966.9
Total revenues	—			—			8,420.40			—			8,420.40
Cost of sales and fuel	—			—			7,214.30			—			7,214.30
Net margin	—			—			1,206.10			—			1,206.10
Operating expenses
Operations and maintenance	—			—			338.4			—			338.4
Depreciation and amortization	—			—			174.1			—			174.1
General taxes	—			—			46.2			—			46.2
Total operating expenses	—			—			558.7			—			558.7
Gain (loss) on sale of assets	—			—			0.4			—			0.4
Operating income	—			—			647.8			—			647.8
Equity earnings from investments	575.3			575.3			31.6			(1,102.5		)	79.7
Allowance for equity funds used during	—			—			21.2			—			21.2
construction
Other income (expense), net	205.1			205.1			5.8			(410.2		)	5.8
Interest expense, net	(205.1		)	(205.1		)	(171.1		)	410.2			(171.1		)
Income before income taxes	575.3			575.3			535.3			(1,102.5		)	583.4
Income taxes	—			—			(7.9		)	—			(7.9		)
Net income	575.3			575.3			527.4			(1,102.5		)	575.5
Less: Net income attributable to noncontrolling	—			—			0.2			—			0.2
interests
Net income attributable to ONEOK Partners, L.P.	$	575.3		$	575.3		$	527.2		$	(1,102.5	)	$	575.3
Condensed Consolidating Statements of Comprehensive Income	'
	Condensed Consolidating Statements of Comprehensive Income
		Three Months Ended September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Net income	$	167.2		$	167.2		$	152.9		$	(320.0	)	$	167.3
	Other comprehensive income (loss)
	Unrealized gains (losses) on derivatives	7.4			17.1			17.1			(34.2		)	7.4
	Realized (gains) losses on derivatives recognized in	3			0.4			0.4			(0.8		)	3
	net income
	Total other comprehensive income (loss)	10.4			17.5			17.5			(35.0		)	10.4
	Comprehensive income	177.6			184.7			170.4			(355.0		)	177.7
	Less: Comprehensive income attributable to	—			—			0.1			—			0.1
	noncontrolling interests
	Comprehensive income attributable to	$	177.6		$	184.7		$	170.3		$	(355.0	)	$	177.6
	ONEOK Partners, L.P.
		Three Months Ended September 30, 2013
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Net income	$	216.3		$	216.3		$	199.9		$	(416.1	)	$	216.4
	Other comprehensive income (loss)
	Unrealized gains (losses) on derivatives	(3.6		)	(10.3		)	(10.3		)	20.6			(3.6		)
	Realized (gains) losses on derivatives recognized in	2.2			(0.4		)	(0.4		)	0.8			2.2
	net income
	Total other comprehensive income (loss)	(1.4		)	(10.7		)	(10.7		)	21.4			(1.4		)
	Comprehensive income	214.9			205.6			189.2			(394.7		)	215
	Less: Comprehensive income attributable to	—			—			0.1			—			0.1
	noncontrolling interests
	Comprehensive income attributable to	$	214.9		$	205.6		$	189.1		$	(394.7	)	$	214.9
	ONEOK Partners, L.P.
		Nine Months Ended September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Net income	$	647.1		$	647.1		$	593.7		$	(1,240.6	)	$	647.3
	Other comprehensive income (loss)
	Unrealized gains (losses) on derivatives	(81.6		)	(24.7		)	(24.7		)	49.4			(81.6		)
	Realized (gains) losses on derivatives recognized in	39.8			32			32			(64.0		)	39.8
	net income
	Total other comprehensive income (loss)	(41.8		)	7.3			7.3			(14.6		)	(41.8		)
	Comprehensive income	605.3			654.4			601			(1,255.2		)	605.5
	Less: Comprehensive income attributable to	—			—			0.2			—			0.2
	noncontrolling interests
	Comprehensive income attributable to	$	605.3		$	654.4		$	600.8		$	(1,255.2	)	$	605.3
	ONEOK Partners, L.P.
		Nine Months Ended September 30, 2013
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Net income	$	575.3		$	575.3		$	527.4		$	(1,102.5	)	$	575.5
	Other comprehensive income (loss)
	Unrealized gains (losses) on derivatives	38.8			3.1			3.1			(6.2		)	38.8
	Realized (gains) losses on derivatives recognized in	3.2			(4.2		)	(4.2		)	8.4			3.2
	net income
	Total other comprehensive income (loss)	42			(1.1		)	(1.1		)	2.2			42
	Comprehensive income	617.3			574.2			526.3			(1,100.3		)	617.5
	Less: Comprehensive income attributable to	—			—			0.2			—			0.2
	noncontrolling interests
Comprehensive income attributable to	$	617.3		$	574.2		$	526.1		$	(1,100.3	)	$	617.3
ONEOK Partners, L.P.
Condensed Consolidating Balance Sheets	'
	Condensed Consolidating Balance Sheets
		September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
	Assets	(Millions of dollars)
	Current assets
	Cash and cash equivalents	$	—		$	54		$	—		$	—		$	54
	Accounts receivable, net	—			—			951.6			—			951.6
	Affiliate receivables	—			—			5.9			—			5.9
	Natural gas and natural gas liquids in storage	—			—			338.3			—			338.3
	Commodity imbalances	—			—			74.3			—			74.3
	Other current assets	13.1			—			70.7			—			83.8
	Total current assets	13.1			54			1,440.80			—			1,507.90
	Property, plant and equipment
	Property, plant and equipment	—			—			11,951.50			—			11,951.50
	Accumulated depreciation and amortization	—			—			1,837.10			—			1,837.10
	Net property, plant and equipment	—			—			10,114.40			—			10,114.40
	Investments and other assets
	Investments in unconsolidated affiliates	4,222.70			5,179.50			738.9			(9,012.6		)	1,128.50
	Intercompany notes receivable	7,612.00			6,601.20			—			(14,213.2		)	—
	Goodwill and intangible assets	—			—			825.3			—			825.3
	Other assets	56			—			22.1			—			78.1
	Total investments and other assets	11,890.70			11,780.70			1,586.30			(23,225.8		)	2,031.90
	Total assets	$	11,903.80		$	11,834.70		$	13,141.50		$	(23,225.8	)	$	13,654.20
	Liabilities and equity
	Current liabilities
	Current maturities of long-term debt	$	—		$	—		$	7.7		$	—		$	7.7
	Accounts payable	—			—			1,216.10			—			1,216.10
	Affiliate payables	—			—			29.4			—			29.4
	Commodity imbalances	—			—			171.2			—			171.2
	Accrued interest	88			—			—			—			88
	Other current liabilities	23.3			—			136			—			159.3
	Total current liabilities	111.3			—			1,560.40			—			1,671.70
	Intercompany debt	—			7,612.00			6,601.20			(14,213.2		)	—
	Long-term debt, excluding current maturities	5,986.20			—			53.8			—			6,040.00
	Deferred credits and other liabilities	—			—			131.8			—			131.8
	Commitments and contingencies
	Equity
	Equity excluding noncontrolling interests in	5,806.30			4,222.70			4,789.90			(9,012.6		)	5,806.30
	consolidated subsidiaries
	Noncontrolling interests in consolidated	—			—			4.4			—			4.4
	subsidiaries
	Total equity	5,806.30			4,222.70			4,794.30			(9,012.6		)	5,810.70
	Total liabilities and equity	$	11,903.80		$	11,834.70		$	13,141.50		$	(23,225.8	)	$	13,654.20
		December 31, 2013
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
	Assets	(Millions of dollars)
	Current assets
	Cash and cash equivalents	$	—		$	134.5		$	—		$	—		$	134.5
	Accounts receivable, net	—			—			1,103.10			—			1,103.10
	Affiliate receivables	—			—			9.2			—			9.2
	Natural gas and natural gas liquids in storage	—			—			188.3			—			188.3
	Commodity imbalances	—			—			80.5			—			80.5
	Other current assets	4.8			—			62.7			—			67.5
	Total current assets	4.8			134.5			1,443.80			—			1,583.10
	Property, plant and equipment
	Property, plant and equipment	—			—			10,755.00			—			10,755.00
	Accumulated depreciation and amortization	—			—			1,652.60			—			1,652.60
	Net property, plant and equipment	—			—			9,102.40			—			9,102.40
	Investments and other assets
Investments in unconsolidated affiliates	4,336.40			4,593.10			825.6			(8,525.3		)	1,229.80
Intercompany notes receivable	6,638.30			6,247.10			—			(12,885.4		)	—
Goodwill and intangible assets	—			—			832.2			—			832.2
Other assets	92.7			—			22.4			—			115.1
Total investments and other assets	11,067.40			10,840.20			1,680.20			(21,410.7		)	2,177.10
Total assets	$	11,072.20		$	10,974.70		$	12,226.40		$	(21,410.7	)	$	12,862.60
Liabilities and equity
Current liabilities
Current maturities of long-term debt	$	—		$	—		$	7.7		$	—		$	7.7
Accounts payable	—			—			1,255.40			—			1,255.40
Affiliate payables	—			—			47.5			—			47.5
Commodity imbalances	—			—			213.6			—			213.6
Accrued interest	92.7			—			—			—			92.7
Other current liabilities	—			—			89.1			—			89.1
Total current liabilities	92.7			—			1,613.30			—			1,706.00
Intercompany debt	—			6,638.30			6,247.10			(12,885.4		)	—
Long-term debt, excluding current maturities	5,985.30			—			59.6			—			6,044.90
Deferred credits and other liabilities	—			—			113			—			113
Commitments and contingencies
Equity
Equity excluding noncontrolling interests in	4,994.20			4,336.40			4,188.90			(8,525.3		)	4,994.20
consolidated subsidiaries
Noncontrolling interests in consolidated	—			—			4.5			—			4.5
subsidiaries
Total equity	4,994.20			4,336.40			4,193.40			(8,525.3		)	4,998.70
Total liabilities and equity	$	11,072.20		$	10,974.70		$	12,226.40		$	(21,410.7	)	$	12,862.60
Condensed Consolidating Statements of Cash Flows	'
	Condensed Consolidating Statements of Cash Flows
		Nine Months Ended September 30, 2014
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Operating activities
	Cash provided by operating activities	$	815.1		$	53.7		$	786.4		$	(768.1	)	$	887.1
	Investing activities
	Capital expenditures (less allowance for equity	—			—			(1,173.0		)	—			(1,173.0		)
	funds used during construction)
	Acquisition	—			—			(14.0		)	—			(14.0		)
	Contributions to unconsolidated affiliates	—			—			(1.0		)	—			(1.0		)
	Distributions received from unconsolidated	—			14.5			10.4			—			24.9
	affiliates
	Proceeds from sale of assets	—			—			2.4			—			2.4
	Cash provided by (used in) investing activities	—			14.5			(1,175.2		)	—			(1,160.7		)
	Financing activities
	Cash distributions:
	General and limited partners	(768.1		)	(768.1		)	—			768.1			(768.1		)
	Noncontrolling interests	—			—			(0.4		)	—			(0.4		)
	Borrowing of notes payable, net	—			—			—			—			—
	Intercompany borrowings (advances), net	(1,014.3		)	619.4			394.9			—			—
	Repayment of long-term debt	—			—			(5.7		)	—			(5.7		)
	Issuance of common units, net of issuance costs	947.5			—			—			—			947.5
	Contribution from general partner	19.8			—			—			—			19.8
	Cash provided by (used in) financing activities	(815.1		)	(148.7		)	388.8			768.1			193.1
	Change in cash and cash equivalents	—			(80.5		)	—			—			(80.5		)
	Cash and cash equivalents at beginning of	—			134.5			—			—			134.5
	period
	Cash and cash equivalents at end of period	$	—		$	54		$	—		$	—		$	54
		Nine Months Ended September 30, 2013
	(Unaudited)	Parent			Guarantor			Combined			Consolidating			Total
					Subsidiary			Non-Guarantor			Entries
								Subsidiaries
		(Millions of dollars)
	Operating activities
	Cash provided by operating activities	$	641.5		$	48.1		$	634.5		$	(670.0	)	$	654.1
	Investing activities
	Capital expenditures (less allowance for equity	—			—			(1,373.9		)	—			(1,373.9		)
	funds used during construction)
	Acquisition	—			—			(304.9		)	—			(304.9		)
	Contributions to unconsolidated affiliates	—			—			(4.6		)	—			(4.6		)
	Distributions received from unconsolidated	—			17.3			7.6			—			24.9
	affiliates
	Proceeds from sale of assets	—			—			0.7			—			0.7
	Cash provided by (used in) investing activities	—			17.3			(1,675.1		)	—			(1,657.8		)
	Financing activities
	Cash distributions:
	General and limited partners	(670.0		)	(670.0		)	—			670			(670.0		)
	Noncontrolling interests	—			—			(0.4		)	—			(0.4		)
	Borrowings of notes payable, net	47			—			—			—			47
	Issuance of long-term debt, net of discounts	1,247.80			—			—			—			1,247.80
	Long-term debt financing costs	(10.2		)	—			—			—			(10.2		)
	Intercompany borrowings (advances), net	(1,837.2		)	790.5			1,046.70			—			—
	Repayment of long-term debt	—			—			(5.7		)	—			(5.7		)
	Issuance of common units, net of issuance costs	569.2			—			—			—			569.2
	Contribution from general partner	11.9			—			—			—			11.9
	Cash provided by (used in) financing activities	(641.5		)	120.5			1,040.60			670			1,189.60
	Change in cash and cash equivalents	—			185.9			—			—			185.9
	Cash and cash equivalents at beginning of	—			537.1			—			—			537.1
	period
	Cash and cash equivalents at end of period	$	—		$	723		$	—		$	—		$	723

ACQUISITIONS_ACQUISITIONS_Deta

ACQUISITIONS ACQUISITIONS (Details) (USD $)	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2014	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Sep. 30, 2014
			Partnership Credit Agreement [Member]	West Texas LPG Acquisition [Member]	Sage Creek Acquisition [Member]	Sage Creek Acquisition [Member]	Sage Creek Acquisition [Member]	Sage Creek Acquisition [Member]
				Subsequent Event [Member]			Natural Gas Gathering And Processing [Member]	Natural Gas Liquids [Member]
Business Combination, Separately Recognized Transactions [Line Items]	'	'	'	'	'	'	'	'
Maximum Amount Of Commercial Paper	$1,700,000,000	$1,200,000,000	'	'	'	'	'	'
Line of Credit Facility, Maximum Borrowing Capacity	'	'	1,700,000,000	'	'	'	'	'
Payments to Acquire Businesses, Gross	'	'	'	800,000,000	'	'	'	'
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest	'	'	'	'	'	305,000,000	152,000,000	153,000,000
Goodwill	'	'	'	'	$92,000,000	'	'	'

FAIR_VALUE_MEASUREMENTS_Part_1

FAIR VALUE MEASUREMENTS - Part 1 (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash collateral held	$0	$0
Cash collateral posted	0	0
Fair Value, Measurements, Recurring [Member]	'	'
Derivative assets	'	'
Commodity contracts - financial	6,528	4,723
Commodity contracts - physical	2,571	1,077
Interest-rate contracts	20,962	54,503
Total derivative assets	30,061	60,303
Derivative liabilities	'	'
Commodity contracts - financial	0	-3,361
Commodity contracts - physical	-354	-2,517
Interest-rate contracts	-23,308	'
Total derivative liabilities	-23,662	-5,878
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Derivative assets	'	'
Commodity contracts - financial	9,093	0
Commodity contracts - physical	0	0
Interest-rate contracts	0	0
Total derivative assets	9,093	0
Derivative liabilities	'	'
Commodity contracts - financial	-83	0
Commodity contracts - physical	0	0
Interest-rate contracts	0	'
Total derivative liabilities	-83	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Derivative assets	'	'
Commodity contracts - financial	439	3,657
Commodity contracts - physical	0	0
Interest-rate contracts	20,962	54,503
Total derivative assets	21,401	58,160
Derivative liabilities	'	'
Commodity contracts - financial	0	-2,953
Commodity contracts - physical	0	0
Interest-rate contracts	-23,308	'
Total derivative liabilities	-23,308	-2,953
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Derivative assets	'	'
Commodity contracts - financial	0	2,812
Commodity contracts - physical	2,900	2,023
Interest-rate contracts	0	0
Total derivative assets	2,900	4,835
Derivative liabilities	'	'
Commodity contracts - financial	-2,921	-2,154
Commodity contracts - physical	-683	-3,463
Interest-rate contracts	0	'
Total derivative liabilities	-3,604	-5,617
Fair Value, Measurements, Recurring [Member] | Total Gross, Fair Value Disclosure [Member]	'	'
Derivative assets	'	'
Commodity contracts - financial	9,532	6,469
Commodity contracts - physical	2,900	2,023
Interest-rate contracts	20,962	54,503
Total derivative assets	33,394	62,995
Derivative liabilities	'	'
Commodity contracts - financial	-3,004	-5,107
Commodity contracts - physical	-683	-3,463
Interest-rate contracts	-23,308	'
Total derivative liabilities	-26,995	-8,570
Fair Value, Measurements, Recurring [Member] | Netting [Member]	'	'
Derivative assets	'	'
Commodity contracts - financial	-3,004	-1,746
Commodity contracts - physical	-329	-946
Interest-rate contracts	0	0
Total derivative assets	-3,333	-2,692
Derivative liabilities	'	'
Commodity contracts - financial	3,004	1,746
Commodity contracts - physical	329	946
Interest-rate contracts	0	'
Total derivative liabilities	$3,333	$2,692

FAIR_VALUE_MEASUREMENTS_Part_2

FAIR VALUE MEASUREMENTS - Part 2 (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Fair Value, Assets And Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]	'	'	'	'
Transfers between levels	$0	$0	$0	$0
Derivative Financial Instruments, Assets Liabilities [Member]	'	'	'	'
Fair Value, Assets And Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]	'	'	'	'
Net assets (liabilities) at beginning of period	-1,313	7,682	-782	-2,423
Total realized/unrealized gains (losses): [Abstract]	'	'	'	'
Included in earnings	207	0	-688	0
Included in other comprehensive income (loss)	402	-7,181	-2,968	2,924
Purchases, issuances and settlements	0	0	3,734	0
Net assets (liabilities) at end of period	($704)	$501	($704)	$501

FAIR_VALUE_MEASUREMENTS_Part_3

FAIR VALUE MEASUREMENTS - Part 3 (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Billions, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Senior notes, fair value	$6.70	$6.50
Reported Value Measurement [Member]	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Senior notes, book value	$6	$6.10

RISK_MANAGEMENT_AND_HEDGING_AC3

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES Part 1 (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Derivative [Line Items]	'	'
Assets	$33,394,000	$62,995,000
(Liabilities)	-26,995,000	-8,570,000
Net unrealized loss in accumulated other comprehensive income (loss)	100,584,000	58,837,000
Natural Gas Liquids [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	0	0
Natural Gas Pipelines [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	0	0
Cash Flow Hedging [Member] | Fixed Price [Member] | Natural Gas [Member] | Swap [Member] | Purchased [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	0	0
Cash Flow Hedging [Member] | Fixed Price [Member] | Natural Gas [Member] | Swap [Member] | Sold [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	-31,200	-48,100
Cash Flow Hedging [Member] | Fixed Price [Member] | Crude oil and NGLs [Member] | Forwards and Swaps Contracts [Member] | Purchased [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	0	0
Cash Flow Hedging [Member] | Fixed Price [Member] | Crude oil and NGLs [Member] | Forwards and Swaps Contracts [Member] | Sold [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	-1.7	-4
Cash Flow Hedging [Member] | Basis [Member] | Natural Gas [Member] | Swap [Member] | Purchased [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	0	0
Cash Flow Hedging [Member] | Basis [Member] | Natural Gas [Member] | Swap [Member] | Sold [Member]	'	'
Derivative [Line Items]	'	'
Notional amounts	-31,200	-48,100
Cash Flow Hedging [Member] | Interest Rate Forward Starting Swaps [Member] | Purchased [Member]	'	'
Derivative [Line Items]	'	'
Derivative, notional amount designated as cash flow hedges	900,000,000	400,000,000
Cash Flow Hedging [Member] | Interest Rate Forward Starting Swaps [Member] | Sold [Member]	'	'
Derivative [Line Items]	'	'
Derivative, notional amount designated as cash flow hedges	0	0
Commodity Contract [Member] | Cash Flow Hedging [Member]	'	'
Derivative [Line Items]	'	'
Cash flow hedge gain to be reclassified within 15 months	6,300,000	'
Amount of gains recognized in the next 12 months	5,400,000	'
Amount of gains to be reclassified after 12 months	900,000	'
Interest Rate Contract [Member] | Cash Flow Hedging [Member]	'	'
Derivative [Line Items]	'	'
Amount of loss deferred in accumulated other comprehensive income (loss) attributable to settled interest-rate swaps	102,000,000	'
Amount of losses to be reclassified over the next 12 months	10,600,000	'
Designated as Hedging Instrument [Member]	'	'
Derivative [Line Items]	'	'
Assets	33,048,000	62,036,000
(Liabilities)	-26,920,000	-8,570,000
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]	'	'
Derivative [Line Items]	'	'
Assets	20,962,000	54,503,000
(Liabilities)	-23,308,000	0
Designated as Hedging Instrument [Member] | Financial Derivative Instrument [Member] | Commodity Contract [Member]	'	'
Derivative [Line Items]	'	'
Assets	9,532,000	6,469,000
(Liabilities)	-3,004,000	-5,107,000
Designated as Hedging Instrument [Member] | Physical Derivative Instrument [Member] | Commodity Contract [Member]	'	'
Derivative [Line Items]	'	'
Assets	2,554,000	1,064,000
(Liabilities)	-608,000	-3,463,000
Not Designated as Hedging Instrument [Member]	'	'
Derivative [Line Items]	'	'
Assets	346,000	959,000
(Liabilities)	-75,000	0
Not Designated as Hedging Instrument [Member] | Physical Derivative Instrument [Member] | Commodity Contract [Member]	'	'
Derivative [Line Items]	'	'
Assets	346,000	959,000
(Liabilities)	-75,000	0
Other Assets [Member] | Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]	'	'
Derivative [Line Items]	'	'
Derivative, notional amount designated as cash flow hedges	900,000,000	'
Notional amount of cash flow hedge instruments greater than 12 months	$400,000,000	'

RISK_MANAGEMENT_AND_HEDGING_AC4

RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES, Part 2 (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Derivative, Net Liability Position, Aggregate Fair Value	$0	'	$0	'
Commodity Contract [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income (effective portion)	355,000	-361,000	31,961,000	-4,172,000
Interest Rate Contract [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income (effective portion)	2,648,000	2,565,000	7,884,000	7,445,000
Cash Flow Hedging [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) recognized in other comprehensive income (loss) (effective portion)	7,378,000	-3,596,000	-81,592,000	38,786,000
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income (effective portion)	-3,003,000	-2,204,000	-39,845,000	-3,273,000
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0	0	0	0
Cash Flow Hedging [Member] | Commodity Contract [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) recognized in other comprehensive income (loss) (effective portion)	17,133,000	-10,317,000	-24,743,000	3,060,000
Cash Flow Hedging [Member] | Commodity Contract [Member] | Sales [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income (effective portion)	-355,000	361,000	-31,961,000	4,172,000
Cash Flow Hedging [Member] | Interest Rate Contract [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) recognized in other comprehensive income (loss) (effective portion)	-9,755,000	6,721,000	-56,849,000	35,726,000
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Interest Expense [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Total gain (loss) reclassified from accumulated other comprehensive income (loss) into net income (effective portion)	($2,648,000)	($2,565,000)	($7,884,000)	($7,445,000)

CREDIT_FACILITY_AND_SHORTTERM_1

CREDIT FACILITY AND SHORT-TERM NOTES PAYABLE (Details) (USD $)	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2014
			Partnership Credit Agreement [Member]
Line of Credit Facility [Line Items]	'	'	'
Total short-term borrowings authorized by general partner's Board of Directors	'	'	$2,500,000,000
Commercial Paper	'	'	0
Letters of Credit Outstanding, Amount	'	'	14,000,000
Short-term Bank Loans and Notes Payable	'	'	0
Line of Credit Facility, Maximum Borrowing Capacity	'	'	1,700,000,000
Partnership Credit Agreement sublimit for issuance of standby letters of credit	'	'	100,000,000
line of credit facility swingline subfacility	'	'	150,000,000
Option to increase borrowing capacity	'	'	2,400,000,000
Maximum Amount Of Commercial Paper	1,700,000,000	1,200,000,000	'
Interest rate description	'	'	'borrowings, if any, will accrue at LIBOR plus 117.5 basis points
Annual fee description	'	'	'the annual facility fee is 20 basis points
Indebtedness To Adjusted EBITDA Maximum	'	'	5
Acquisition price threshold for increase in permitted debt to EBITDA covenant ratio	'	'	$25,000,000
Indebtedness To Adjusted EBITDA From Acquisitions Maximum	'	'	5.5
Indebtedness To Adjusted EBITDA Current	'	'	3.4

LONG_TERM_DEBT_LONGTERM_DEBT_D

LONG TERM DEBT LONG-TERM DEBT (Details) (Partnership Interest [Member], USD $)	9 Months Ended
	Sep. 30, 2013
Senior Notes [Member]	'
Debt Instrument [Line Items]	'
Senior Notes, Noncurrent	$1,250,000,000
Proceeds from Debt, Net of Issuance Costs	1,240,000,000
Note Payable from Public Offering Due 2018 [Member]	'
Debt Instrument [Line Items]	'
Long-term Debt, Gross	425,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.20%
Note Payable from Public Offering Due 2023 [Member]	'
Debt Instrument [Line Items]	'
Long-term Debt, Gross	425,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Note Payable from Public Offering Due 2043 [Member]	'
Debt Instrument [Line Items]	'
Long-term Debt, Gross	$400,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.20%

EQUITY_Details

EQUITY (Details) (USD $)

3 Months Ended

9 Months Ended

12 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2014

Sep. 30, 2013

Mar. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Mar. 31, 2013

Sep. 30, 2014

General Partner [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Declared [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Distribution Paid [Member]

Issued Under Public Offering [Domain]

Issued Under Public Offering [Domain]

Issued Under Equity Distribution Agreement [Member]

Issued Under Equity Distribution Agreement [Member]

Issued Under Equity Distribution Agreement [Member]

General Partner [Member]

General Partner [Member]

General Partner [Member]

General Partner [Member]

Limited Partner [Member]

Limited Partner [Member]

Limited Partner [Member]

Limited Partner [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

General Partner [Member]

General Partner [Member]

General Partner [Member]

General Partner [Member]

Limited Partner [Member]

Limited Partner [Member]

Limited Partner [Member]

Limited Partner [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

Schedule of Capitalization, Equity [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Limited Liability Company (LLC) or Limited Partneship (LP), Managing Member or General Partner, Ownership Interest

'

'

'

'

'

2.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of common units owned by related party (in number of units)

19,800,000

'

'

19,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

General partnership ownership interest (in hundredths)

'

'

'

38.30%

41.20%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Partners' Capital Account, Units, Sold in Public Offering

13,900,000

11,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Public offering price of common units

$52.94

$49.61

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Partners capital account units sold under equity distribution agreement

1,400,000

'

300,000

4,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from sale of interest in partnership units

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$714,500,000

$553,400,000

$81,300,000

$16,300,000

$245,400,000

Contributions from General Partner

15,000,000

11,600,000

'

19,760,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Distribution per unit

'

'

'

'

'

'

$0.78

$0.73

$2.28

$2.16

'

'

'

'

'

'

'

'

'

'

'

'

$0.76

$0.72

$2.23

$2.15

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Distribution Made To Member Or Limited Parter Annualized Quarterly Distribution

'

'

'

'

'

'

3.1

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

General partner distributions

'

'

'

'

'

'

'

'

'

'

5,683,000

4,795,000

16,195,000

13,776,000

'

'

'

'

'

'

'

'

'

'

'

'

5,501,000

4,512,000

15,361,000

13,399,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Incentive distributions

'

'

'

'

'

'

'

'

'

'

84,452,000

67,017,000

236,744,000

191,226,000

'

'

'

'

'

'

'

'

'

'

'

'

80,381,000

62,634,000

220,547,000

184,647,000

'

'

'

'

'

'

'

'

'

'

'

'

'

General Partners' Capital Account, Period Distribution Amount

'

'

'

'

'

'

'

'

'

'

90,135,000

71,812,000

252,939,000

205,002,000

'

'

'

'

'

'

'

'

'

'

'

'

85,882,000

67,146,000

235,908,000

198,046,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Limited partner distributions

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

71,911,000

67,271,000

211,557,000

200,422,000

'

'

'

'

'

'

'

'

'

'

'

'

70,519,000

66,807,000

207,381,000

199,031,000

'

'

'

'

'

Partners capital account distributions to other unit holders

'

'

'

'

'

'

'

'

'

'

'

'

'

'

122,105,000

100,650,000

345,255,000

283,365,000

'

'

'

'

'

'

'

'

'

'

'

'

118,644,000

91,676,000

324,805,000

272,904,000

'

'

'

'

'

'

'

'

'

Total distributions

'

'

'

$768,447,000

'

'

$284,151,000

$239,733,000

$809,751,000

$688,789,000

'

'

'

'

'

'

'

'

'

'

'

'

$275,045,000

$225,629,000

$768,094,000

$669,981,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Distribution Made To Member Or Limited Parter Change From Prior Quarter

'

'

'

'

'

'

0.015

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Distribution Made to Member or Limited Partner, Distribution Date

'

'

'

'

'

'

14-Nov-14

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Distribution Made to Member or Limited Partner, Date of Record

'

'

'

'

'

'

3-Nov-14

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

ACCUMULATED_OTHER_COMPREHENSIV2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Accumulated other comprehensive loss - January 1, 2014	'	'	($58,837)	'
Other comprehensive income (loss) before reclassifications	7,378	-3,596	-81,592	38,786
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	3,003	2,204	39,845	3,273
Net current-period other comprehensive income (loss) attributable to ONEOK Partners, L.P.	10,381	-1,392	-41,747	42,059
Accumulated other comprehensive loss - September 30, 2014	-100,584	'	-100,584	'
Cash Flow Hedging [Member]	'	'	'	'
Amounts reclassified from accumulated other comprehensive income (loss)	3,003	2,204	39,845	3,273
Commodity Contract [Member]	'	'	'	'
Amounts reclassified from accumulated other comprehensive income (loss)	-355	361	-31,961	4,172
Commodity Contract [Member] | Sales [Member] | Cash Flow Hedging [Member]	'	'	'	'
Amounts reclassified from accumulated other comprehensive income (loss)	355	-361	31,961	-4,172
Interest Rate Contract [Member]	'	'	'	'
Amounts reclassified from accumulated other comprehensive income (loss)	-2,648	-2,565	-7,884	-7,445
Interest Rate Contract [Member] | Interest Expense [Member] | Cash Flow Hedging [Member]	'	'	'	'
Amounts reclassified from accumulated other comprehensive income (loss)	$2,648	$2,565	$7,884	$7,445

LIMITED_PARTNERS_NET_INCOME_PE1

LIMITED PARTNERS' NET INCOME PER UNIT (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]	'	'
General partnership ownership interest (in hundredths)	38.30%	41.20%
Number of days notice of withdrawal of waiver	90	'
General Partner [Member]	'	'
Schedule of Equity Method Investments [Line Items]	'	'
Limited Liability Company (LLC) or Limited Partneship (LP), Managing Member or General Partner, Ownership Interest	2.00%	'

UNCONSOLIDATED_AFFILIATES_Deta

UNCONSOLIDATED AFFILIATES (Details) (USD $)

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Jun. 30, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Northern Border Pipeline [Member]

Northern Border Pipeline [Member]

Northern Border Pipeline [Member]

Northern Border Pipeline [Member]

Overland Pass Pipeline Company [Member]

Overland Pass Pipeline Company [Member]

Overland Pass Pipeline Company [Member]

Overland Pass Pipeline Company [Member]

Fort Union Gas Gathering LLC [Member]

Fort Union Gas Gathering LLC [Member]

Fort Union Gas Gathering LLC [Member]

Fort Union Gas Gathering LLC [Member]

Bighorn Gas Gathering LLC [Member]

Bighorn Gas Gathering LLC [Member]

Bighorn Gas Gathering LLC [Member]

Bighorn Gas Gathering LLC [Member]

Bighorn Gas Gathering LLC [Member]

Other Unconsolidated Affiliate [Member]

Other Unconsolidated Affiliate [Member]

Other Unconsolidated Affiliate [Member]

Other Unconsolidated Affiliate [Member]

Unconsolidated Affiliates [Member]

Unconsolidated Affiliates [Member]

Unconsolidated Affiliates [Member]

Unconsolidated Affiliates [Member]

Schedule of Equity Method Investments [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Costs and operating expenses with equity method investees

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$15,000,000

$15,900,000

$43,500,000

$36,300,000

Equity earnings (loss) from investments

-52,347,000

27,468,000

6,747,000

79,744,000

'

14,371,000

16,464,000

53,657,000

48,133,000

3,856,000

5,783,000

12,708,000

14,210,000

4,169,000

2,946,000

12,578,000

9,895,000

-23,472,000

559,000

-24,745,000

1,897,000

'

2,150,000

1,716,000

5,970,000

5,609,000

'

'

'

'

Income (loss) from equity method investments before impairments

1,074,000

27,468,000

60,168,000

79,744,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Other than Temporary Impairment

'

'

-53,400,000

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Other than Temporary Impairment

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

76,400,000

'

'

'

'

'

'

'

'

'

'

Investments in unconsolidated affiliates

1,128,509,000

1,201,873,000

1,128,509,000

1,201,873,000

1,229,838,000

'

'

'

'

'

'

'

'

'

'

'

'

8,800,000

'

8,800,000

'

'

'

'

'

'

'

'

'

'

Equity method goodwill included in Bighorn Gas Gathering, LLC

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

23,000,000

'

'

'

'

'

'

'

'

Income Statement [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Operating revenues

126,218,000

131,959,000

403,006,000

391,912,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Operating expenses

123,620,000

63,971,000

247,169,000

189,366,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net income

-5,119,000

61,630,000

134,432,000

185,580,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Distributions paid to us

$31,574,000

$34,409,000

$109,223,000

$103,913,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

RELATEDPARTY_TRANSACTIONS_Deta

RELATED-PARTY TRANSACTIONS (Details) (USD $)

3 Months Ended

9 Months Ended

12 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

In Thousands, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

General Partner [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

General Partner [Member]

General Partner [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

ONEOK [Member]

Related Party Transaction [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Contributions from General Partner

$15,000

$11,600

$19,760

'

'

'

'

'

'

$19,760

$12,000

'

'

'

'

General partnership ownership interest (in hundredths)

'

'

38.30%

41.20%

'

'

'

'

'

'

'

'

'

'

'

Revenues

'

'

'

'

'

'

'

'

'

'

'

0

81,324

53,526

255,298

Expenses [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cost of sales and fuel

'

'

'

'

'

'

'

'

'

'

'

0

9,562

10,835

27,855

Administrative and general expenses

'

'

'

'

'

'

'

'

'

'

'

84,221

58,549

240,172

192,906

Total expenses

'

'

'

'

'

$84,221

$68,111

$251,007

$220,761

'

'

'

'

'

'

Limited Liability Company (LLC) or Limited Partneship (LP), Managing Member or General Partner, Ownership Interest

'

'

'

'

2.00%

'

'

'

'

'

'

'

'

'

'

SEGMENTS_Details

SEGMENTS (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]	'	'	'	'	'
Disclosure of Major Customers	'we had no single customer from which we received 10 percent or more of our consolidated revenues.	'we had no single customer from which we received 10 percent or more of our consolidated revenues.	'we had no single customer from which we received 10 percent or more of our consolidated revenues.	'we had no single customer from which we received 10 percent or more of our consolidated revenues.	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	$3,119,369	$3,134,733	$9,347,407	$8,420,359	'
Net margin	536,165	423,574	1,540,132	1,206,126	'
Operating costs	170,785	122,362	481,613	384,602	'
Depreciation and amortization	73,901	61,182	212,083	174,086	'
Gain (loss) on sale of assets	1,534	22	1,533	342	'
Operating income	293,013	240,052	847,969	647,780	'
Equity earnings (loss) from investments	-52,347	27,468	6,747	79,744	'
Investments in unconsolidated affiliates	1,128,509	1,201,873	1,128,509	1,201,873	1,229,838
Total assets	13,654,242	12,863,326	13,654,242	12,863,326	12,862,608
Noncontrolling interests in consolidated subsidiaries	4,409	4,588	4,409	4,588	4,536
Capital expenditures	380,536	449,072	1,172,950	1,373,904	'
Natural Gas Gathering and Processing [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	777,802	533,017	2,263,292	1,452,790	'
Net margin	178,171	130,882	486,695	365,436	'
Operating costs	64,279	45,074	188,489	141,737	'
Depreciation and amortization	31,327	27,356	89,612	76,366	'
Gain (loss) on sale of assets	324	31	277	344	'
Operating income	82,889	58,483	208,871	147,677	'
Equity earnings (loss) from investments	-71,069	4,668	-60,484	16,228	'
Investments in unconsolidated affiliates	253,930	331,124	253,930	331,124	'
Total assets	4,415,814	3,808,135	4,415,814	3,808,135	'
Noncontrolling interests in consolidated subsidiaries	4,394	4,574	4,394	4,574	'
Capital expenditures	214,917	204,542	506,016	574,509	'
Natural Gas Liquids [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	2,734,520	2,874,848	8,111,642	7,630,631	'
Net margin	282,963	226,242	818,086	632,087	'
Operating costs	76,946	57,010	218,129	171,076	'
Depreciation and amortization	31,661	22,993	89,848	65,033	'
Gain (loss) on sale of assets	-535	7	-572	10	'
Operating income	173,821	146,246	509,537	395,988	'
Equity earnings (loss) from investments	4,351	6,336	13,574	15,383	'
Investments in unconsolidated affiliates	484,238	494,702	484,238	494,702	'
Total assets	7,337,688	6,610,205	7,337,688	6,610,205	'
Noncontrolling interests in consolidated subsidiaries	0	0	0	0	'
Capital expenditures	153,785	230,780	637,524	774,284	'
Natural Gas Liquids [Member] | Natural Gas Liquids for Regulated Segment [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	190,300	147,100	479,400	376,900	'
Net margin	94,300	89,500	263,400	227,800	'
Operating income	46,400	53,400	126,000	129,000	'
Natural Gas Pipelines [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	79,160	75,878	265,938	236,949	'
Net margin	73,399	69,457	242,359	211,224	'
Operating costs	27,998	23,457	82,747	75,608	'
Depreciation and amortization	10,913	10,833	32,623	32,687	'
Gain (loss) on sale of assets	1,746	-16	1,663	-12	'
Operating income	36,234	35,151	128,652	102,917	'
Equity earnings (loss) from investments	14,371	16,464	53,657	48,133	'
Investments in unconsolidated affiliates	390,341	376,047	390,341	376,047	'
Total assets	1,832,368	1,786,413	1,832,368	1,786,413	'
Noncontrolling interests in consolidated subsidiaries	0	0	0	0	'
Capital expenditures	10,650	11,148	25,987	22,497	'
Natural Gas Pipelines [Member] | Natural Gas Pipelines for Regulated Segment [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	65,200	57,500	214,800	182,000	'
Net margin	57,400	52,800	185,500	162,500	'
Operating income	23,400	22,600	84,600	67,000	'
Other and Eliminations	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	-472,113	-349,010	-1,293,465	-900,011	'
Net margin	1,632	-3,007	-7,008	-2,621	'
Operating costs	1,562	-3,179	-7,752	-3,819	'
Depreciation and amortization	0	0	0	0	'
Gain (loss) on sale of assets	-1	0	165	0	'
Operating income	69	172	909	1,198	'
Equity earnings (loss) from investments	0	0	0	0	'
Investments in unconsolidated affiliates	0	0	0	0	'
Total assets	68,372	658,573	68,372	658,573	'
Noncontrolling interests in consolidated subsidiaries	15	14	15	14	'
Capital expenditures	1,184	2,602	3,423	2,614	'
Unaffiliated entity [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	3,119,369	3,053,409	9,293,881	8,165,061	'
Unaffiliated entity [Member] | Natural Gas Gathering and Processing [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	374,403	162,677	1,095,531	466,631	'
Unaffiliated entity [Member] | Natural Gas Liquids [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	2,667,939	2,840,108	7,950,930	7,539,470	'
Unaffiliated entity [Member] | Natural Gas Pipelines [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	77,027	50,624	247,420	158,960	'
Unaffiliated entity [Member] | Other and Eliminations	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	0	0	0	0	'
Affiliated Entity [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	'	81,324	53,526	255,298	'
Affiliated Entity [Member] | Natural Gas Gathering and Processing [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	'	57,400	41,214	179,636	'
Affiliated Entity [Member] | Natural Gas Liquids [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	'	0	0	0	'
Affiliated Entity [Member] | Natural Gas Pipelines [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	'	23,924	12,312	75,662	'
Affiliated Entity [Member] | Other and Eliminations	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	'	0	0	0	'
Operating Segments [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	0	0	0	0	'
Operating Segments [Member] | Natural Gas Gathering and Processing [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	403,399	312,940	1,126,547	806,523	'
Operating Segments [Member] | Natural Gas Liquids [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	66,581	34,740	160,712	91,161	'
Operating Segments [Member] | Natural Gas Liquids [Member] | Natural Gas Liquids for Regulated Segment [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	170,100	130,200	417,000	321,300	'
Operating Segments [Member] | Natural Gas Pipelines [Member]	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	2,133	1,330	6,206	2,327	'
Operating Segments [Member] | Other and Eliminations	'	'	'	'	'
Segment disclosure [Abstract]	'	'	'	'	'
Total revenues	($472,113)	($349,010)	($1,293,465)	($900,011)	'

SUPPLEMENTAL_CONDENSED_CONSOLI2

SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION, Income Statement (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Commodity sales	$2,754,495,000	$2,807,329,000	$8,276,333,000	$7,453,534,000
Services	364,874,000	327,404,000	1,071,074,000	966,825,000
Total revenues	3,119,369,000	3,134,733,000	9,347,407,000	8,420,359,000
Cost of sales and fuel	2,583,204,000	2,711,159,000	7,807,275,000	7,214,233,000
Net margin	536,165,000	423,574,000	1,540,132,000	1,206,126,000
Operating expenses	'	'	'	'
Operations and maintenance	152,533,000	108,978,000	425,715,000	338,353,000
Depreciation and amortization	73,901,000	61,182,000	212,083,000	174,086,000
General taxes	18,252,000	13,384,000	55,898,000	46,249,000
Total operating expenses	244,686,000	183,544,000	693,696,000	558,688,000
Gain on sale of assets	1,534,000	22,000	1,533,000	342,000
Operating income	293,013,000	240,052,000	847,969,000	647,780,000
Equity earnings (loss) from investments	-52,347,000	27,468,000	6,747,000	79,744,000
Allowance for equity funds used during construction	1,723,000	6,429,000	13,947,000	21,172,000
Interest expense	-70,060,000	-57,722,000	-211,344,000	-171,118,000
Income before income taxes	169,912,000	219,391,000	657,266,000	583,360,000
Income taxes	-2,592,000	-2,991,000	-9,967,000	-7,821,000
Net income	167,320,000	216,400,000	647,299,000	575,539,000
Net income attributable to ONEOK Partners, L.P.	167,247,000	216,310,000	647,073,000	575,276,000
Parent [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Commodity sales	0	0	0	0
Services	0	0	0	0
Total revenues	0	0	0	0
Cost of sales and fuel	0	0	0	0
Net margin	0	0	0	0
Operating expenses	'	'	'	'
Operations and maintenance	0	0	0	0
Depreciation and amortization	0	0	0	0
General taxes	0	0	0	0
Total operating expenses	0	0	0	0
Gain on sale of assets	0	'	0	0
Operating income	0	0	0	0
Equity earnings (loss) from investments	167,200,000	216,300,000	647,100,000	575,300,000
Allowance for equity funds used during construction	0	0	0	0
Other income (expense), net	83,100,000	70,600,000	248,900,000	205,100,000
Interest expense	-83,100,000	-70,600,000	-248,900,000	-205,100,000
Income before income taxes	167,200,000	216,300,000	647,100,000	575,300,000
Income taxes	0	0	0	0
Net income	167,200,000	216,300,000	647,100,000	575,300,000
Less: Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to ONEOK Partners, L.P.	167,200,000	216,300,000	647,100,000	575,300,000
Guarantor Subsidiary [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Commodity sales	0	0	0	0
Services	0	0	0	0
Total revenues	0	0	0	0
Cost of sales and fuel	0	0	0	0
Net margin	0	0	0	0
Operating expenses	'	'	'	'
Operations and maintenance	0	0	0	0
Depreciation and amortization	0	0	0	0
General taxes	0	0	0	0
Total operating expenses	0	0	0	0
Gain on sale of assets	0	'	0	0
Operating income	0	0	0	0
Equity earnings (loss) from investments	167,200,000	216,300,000	647,100,000	575,300,000
Allowance for equity funds used during construction	0	0	0	0
Other income (expense), net	83,100,000	70,600,000	248,900,000	205,100,000
Interest expense	-83,100,000	-70,600,000	-248,900,000	-205,100,000
Income before income taxes	167,200,000	216,300,000	647,100,000	575,300,000
Income taxes	0	0	0	0
Net income	167,200,000	216,300,000	647,100,000	575,300,000
Less: Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to ONEOK Partners, L.P.	167,200,000	216,300,000	647,100,000	575,300,000
Combined Non-Guarantor Subsidiaries [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Commodity sales	2,754,500,000	2,807,300,000	8,276,300,000	7,453,500,000
Services	364,900,000	327,400,000	1,071,100,000	966,900,000
Total revenues	3,119,400,000	3,134,700,000	9,347,400,000	8,420,400,000
Cost of sales and fuel	2,583,200,000	2,711,100,000	7,807,300,000	7,214,300,000
Net margin	536,200,000	423,600,000	1,540,100,000	1,206,100,000
Operating expenses	'	'	'	'
Operations and maintenance	152,500,000	109,000,000	425,600,000	338,400,000
Depreciation and amortization	73,900,000	61,200,000	212,100,000	174,100,000
General taxes	18,300,000	13,300,000	55,900,000	46,200,000
Total operating expenses	244,700,000	183,500,000	693,600,000	558,700,000
Gain on sale of assets	1,500,000	'	1,500,000	400,000
Operating income	293,000,000	240,100,000	848,000,000	647,800,000
Equity earnings (loss) from investments	-66,700,000	11,000,000	-46,900,000	31,600,000
Allowance for equity funds used during construction	1,700,000	6,400,000	13,900,000	21,200,000
Other income (expense), net	-2,400,000	3,100,000	0	5,800,000
Interest expense	-70,100,000	-57,700,000	-211,300,000	-171,100,000
Income before income taxes	155,500,000	202,900,000	603,700,000	535,300,000
Income taxes	-2,600,000	-3,000,000	-10,000,000	-7,900,000
Net income	152,900,000	199,900,000	593,700,000	527,400,000
Less: Net income attributable to noncontrolling interests	100,000	100,000	200,000	200,000
Net income attributable to ONEOK Partners, L.P.	152,800,000	199,800,000	593,500,000	527,200,000
Consolidating Entries [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Commodity sales	0	0	0	0
Services	0	0	0	0
Total revenues	0	0	0	0
Cost of sales and fuel	0	0	0	0
Net margin	0	0	0	0
Operating expenses	'	'	'	'
Operations and maintenance	0	0	0	0
Depreciation and amortization	0	0	0	0
General taxes	0	0	0	0
Total operating expenses	0	0	0	0
Gain on sale of assets	0	'	0	0
Operating income	0	0	0	0
Equity earnings (loss) from investments	-320,000,000	-416,100,000	-1,240,600,000	-1,102,500,000
Allowance for equity funds used during construction	0	0	0	0
Other income (expense), net	-166,200,000	-141,200,000	-497,800,000	-410,200,000
Interest expense	166,200,000	141,200,000	497,800,000	410,200,000
Income before income taxes	-320,000,000	-416,100,000	-1,240,600,000	-1,102,500,000
Income taxes	0	0	0	0
Net income	-320,000,000	-416,100,000	-1,240,600,000	-1,102,500,000
Less: Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to ONEOK Partners, L.P.	-320,000,000	-416,100,000	-1,240,600,000	-1,102,500,000
Total [Member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Commodity sales	2,754,500,000	2,807,300,000	8,276,300,000	7,453,500,000
Services	364,900,000	327,400,000	1,071,100,000	966,900,000
Total revenues	3,119,400,000	3,134,700,000	9,347,400,000	8,420,400,000
Cost of sales and fuel	2,583,200,000	2,711,100,000	7,807,300,000	7,214,300,000
Net margin	536,200,000	423,600,000	1,540,100,000	1,206,100,000
Operating expenses	'	'	'	'
Operations and maintenance	152,500,000	109,000,000	425,600,000	338,400,000
Depreciation and amortization	73,900,000	61,200,000	212,100,000	174,100,000
General taxes	18,300,000	13,300,000	55,900,000	46,200,000
Total operating expenses	244,700,000	183,500,000	693,600,000	558,700,000
Gain on sale of assets	1,500,000	'	1,500,000	400,000
Operating income	293,000,000	240,100,000	848,000,000	647,800,000
Equity earnings (loss) from investments	-52,300,000	27,500,000	6,700,000	79,700,000
Allowance for equity funds used during construction	1,700,000	6,400,000	13,900,000	21,200,000
Other income (expense), net	-2,400,000	3,100,000	0	5,800,000
Interest expense	-70,100,000	-57,700,000	-211,300,000	-171,100,000
Income before income taxes	169,900,000	219,400,000	657,300,000	583,400,000
Income taxes	-2,600,000	-3,000,000	-10,000,000	-7,900,000
Net income	167,300,000	216,400,000	647,300,000	575,500,000
Less: Net income attributable to noncontrolling interests	100,000	100,000	200,000	200,000
Net income attributable to ONEOK Partners, L.P.	$167,200,000	$216,300,000	$647,100,000	$575,300,000

SUPPLEMENTAL_CONDENSED_CONSOLI3

SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION, Comprehensive Income (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Net income	$167,320	$216,400	$647,299	$575,539
Other comprehensive income (loss)	'	'	'	'
Unrealized gains (losses) on derivatives	7,378	-3,596	-81,592	38,786
Realized (gains) losses on derivatives recognized in net income	3,003	2,204	39,845	3,273
Total other comprehensive income (loss)	10,381	-1,392	-41,747	42,059
Comprehensive income	177,701	215,008	605,552	617,598
Less: Comprehensive income attributable to noncontrolling interests	73	90	226	263
Comprehensive income attributable to ONEOK Partners, L.P.	177,628	214,918	605,326	617,335
Parent [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Net income	167,200	216,300	647,100	575,300
Other comprehensive income (loss)	'	'	'	'
Unrealized gains (losses) on derivatives	7,400	-3,600	-81,600	38,800
Realized (gains) losses on derivatives recognized in net income	3,000	2,200	39,800	3,200
Total other comprehensive income (loss)	10,400	-1,400	-41,800	42,000
Comprehensive income	177,600	214,900	605,300	617,300
Less: Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to ONEOK Partners, L.P.	177,600	214,900	605,300	617,300
Guarantor Subsidiary [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Net income	167,200	216,300	647,100	575,300
Other comprehensive income (loss)	'	'	'	'
Unrealized gains (losses) on derivatives	17,100	-10,300	-24,700	3,100
Realized (gains) losses on derivatives recognized in net income	400	-400	32,000	-4,200
Total other comprehensive income (loss)	17,500	-10,700	7,300	-1,100
Comprehensive income	184,700	205,600	654,400	574,200
Less: Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to ONEOK Partners, L.P.	184,700	205,600	654,400	574,200
Combined Non-Guarantor Subsidiaries [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Net income	152,900	199,900	593,700	527,400
Other comprehensive income (loss)	'	'	'	'
Unrealized gains (losses) on derivatives	17,100	-10,300	-24,700	3,100
Realized (gains) losses on derivatives recognized in net income	400	-400	32,000	-4,200
Total other comprehensive income (loss)	17,500	-10,700	7,300	-1,100
Comprehensive income	170,400	189,200	601,000	526,300
Less: Comprehensive income attributable to noncontrolling interests	100	100	200	200
Comprehensive income attributable to ONEOK Partners, L.P.	170,300	189,100	600,800	526,100
Consolidating Entries [member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Net income	-320,000	-416,100	-1,240,600	-1,102,500
Other comprehensive income (loss)	'	'	'	'
Unrealized gains (losses) on derivatives	-34,200	20,600	49,400	-6,200
Realized (gains) losses on derivatives recognized in net income	-800	800	-64,000	8,400
Total other comprehensive income (loss)	-35,000	21,400	-14,600	2,200
Comprehensive income	-355,000	-394,700	-1,255,200	-1,100,300
Less: Comprehensive income attributable to noncontrolling interests	0	0	0	0
Comprehensive income attributable to ONEOK Partners, L.P.	-355,000	-394,700	-1,255,200	-1,100,300
Total [Member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Net income	167,300	216,400	647,300	575,500
Other comprehensive income (loss)	'	'	'	'
Unrealized gains (losses) on derivatives	7,400	-3,600	-81,600	38,800
Realized (gains) losses on derivatives recognized in net income	3,000	2,200	39,800	3,200
Total other comprehensive income (loss)	10,400	-1,400	-41,800	42,000
Comprehensive income	177,700	215,000	605,500	617,500
Less: Comprehensive income attributable to noncontrolling interests	100	100	200	200
Comprehensive income attributable to ONEOK Partners, L.P.	$177,600	$214,900	$605,300	$617,300

SUPPLEMENTAL_CONDENSED_CONSOLI4

SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION, Balance Sheet (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Current assets	'	'	'	'
Cash and cash equivalents	$54,029,000	$134,530,000	$723,030,000	$537,074,000
Accounts receivable, net	951,647,000	1,103,130,000	'	'
Affiliate receivables	5,929,000	9,185,000	'	'
Natural gas and natural gas liquids in storage	338,345,000	188,286,000	'	'
Commodity imbalances	74,247,000	80,481,000	'	'
Other current assets	83,773,000	67,491,000	'	'
Total current assets	1,507,970,000	1,583,103,000	'	'
Property, plant and equipment	'	'	'	'
Property, plant and equipment	11,951,450,000	10,755,048,000	'	'
Accumulated depreciation and amortization	1,837,105,000	1,652,648,000	'	'
Net property, plant and equipment	10,114,345,000	9,102,400,000	'	'
Investments and other assets	'	'	'	'
Investments in unconsolidated affiliates	1,128,509,000	1,229,838,000	1,201,873,000	'
Goodwill and intangible assets	825,333,000	832,180,000	'	'
Other assets	78,085,000	115,087,000	'	'
Total investments and other assets	2,031,927,000	2,177,105,000	'	'
Total assets	13,654,242,000	12,862,608,000	12,863,326,000	'
Current liabilities	'	'	'	'
Current maturities of long-term debt	7,650,000	7,650,000	'	'
Notes payable	0	0	'	'
Accounts payable	1,216,107,000	1,255,411,000	'	'
Affiliate payables	29,382,000	47,458,000	'	'
Commodity imbalances	171,249,000	213,577,000	'	'
Accrued interest	88,048,000	92,711,000	'	'
Other current liabilities	159,341,000	89,211,000	'	'
Total current liabilities	1,671,777,000	1,706,018,000	'	'
Long-term debt, excluding current maturities	6,039,997,000	6,044,867,000	'	'
Deferred credits and other liabilities	131,799,000	113,027,000	'	'
Commitments and contingencies	'	'	'	'
Equity	'	'	'	'
Equity excluding noncontrolling interests in consolidated subsidiaries	5,806,260,000	4,994,160,000	'	'
Noncontrolling interests in consolidated subsidiaries	4,409,000	4,536,000	4,588,000	'
Total equity	5,810,669,000	4,998,696,000	'	'
Total liabilities and equity	13,654,242,000	12,862,608,000	'	'
Parent [member]	'	'	'	'
Current assets	'	'	'	'
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0	'	'
Affiliate receivables	0	0	'	'
Natural gas and natural gas liquids in storage	0	0	'	'
Commodity imbalances	0	0	'	'
Other current assets	13,100,000	4,800,000	'	'
Total current assets	13,100,000	4,800,000	'	'
Property, plant and equipment	'	'	'	'
Property, plant and equipment	0	0	'	'
Accumulated depreciation and amortization	0	0	'	'
Net property, plant and equipment	0	0	'	'
Investments and other assets	'	'	'	'
Investments in unconsolidated affiliates	4,222,700,000	4,336,400,000	'	'
Intercompany notes receivable	7,612,000,000	6,638,300,000	'	'
Goodwill and intangible assets	0	0	'	'
Other assets	56,000,000	92,700,000	'	'
Total investments and other assets	11,890,700,000	11,067,400,000	'	'
Total assets	11,903,800,000	11,072,200,000	'	'
Current liabilities	'	'	'	'
Current maturities of long-term debt	0	0	'	'
Accounts payable	0	0	'	'
Affiliate payables	0	0	'	'
Commodity imbalances	0	0	'	'
Accrued interest	88,000,000	92,700,000	'	'
Other current liabilities	23,300,000	0	'	'
Total current liabilities	111,300,000	92,700,000	'	'
Intercompany Debt	0	0	'	'
Long-term debt, excluding current maturities	5,986,200,000	5,985,300,000	'	'
Deferred credits and other liabilities	0	0	'	'
Commitments and contingencies	'	'	'	'
Equity	'	'	'	'
Equity excluding noncontrolling interests in consolidated subsidiaries	5,806,300,000	4,994,200,000	'	'
Noncontrolling interests in consolidated subsidiaries	0	0	'	'
Total equity	5,806,300,000	4,994,200,000	'	'
Total liabilities and equity	11,903,800,000	11,072,200,000	'	'
Guarantor Subsidiary [member]	'	'	'	'
Current assets	'	'	'	'
Cash and cash equivalents	54,000,000	134,500,000	723,000,000	537,100,000
Accounts receivable, net	0	0	'	'
Affiliate receivables	0	0	'	'
Natural gas and natural gas liquids in storage	0	0	'	'
Commodity imbalances	0	0	'	'
Other current assets	0	0	'	'
Total current assets	54,000,000	134,500,000	'	'
Property, plant and equipment	'	'	'	'
Property, plant and equipment	0	0	'	'
Accumulated depreciation and amortization	0	0	'	'
Net property, plant and equipment	0	0	'	'
Investments and other assets	'	'	'	'
Investments in unconsolidated affiliates	5,179,500,000	4,593,100,000	'	'
Intercompany notes receivable	6,601,200,000	6,247,100,000	'	'
Goodwill and intangible assets	0	0	'	'
Other assets	0	0	'	'
Total investments and other assets	11,780,700,000	10,840,200,000	'	'
Total assets	11,834,700,000	10,974,700,000	'	'
Current liabilities	'	'	'	'
Current maturities of long-term debt	0	0	'	'
Accounts payable	0	0	'	'
Affiliate payables	0	0	'	'
Commodity imbalances	0	0	'	'
Accrued interest	0	0	'	'
Other current liabilities	0	0	'	'
Total current liabilities	0	0	'	'
Intercompany Debt	7,612,000,000	6,638,300,000	'	'
Long-term debt, excluding current maturities	0	0	'	'
Deferred credits and other liabilities	0	0	'	'
Commitments and contingencies	'	'	'	'
Equity	'	'	'	'
Equity excluding noncontrolling interests in consolidated subsidiaries	4,222,700,000	4,336,400,000	'	'
Noncontrolling interests in consolidated subsidiaries	0	0	'	'
Total equity	4,222,700,000	4,336,400,000	'	'
Total liabilities and equity	11,834,700,000	10,974,700,000	'	'
Combined Non-Guarantor Subsidiaries [member]	'	'	'	'
Current assets	'	'	'	'
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	951,600,000	1,103,100,000	'	'
Affiliate receivables	5,900,000	9,200,000	'	'
Natural gas and natural gas liquids in storage	338,300,000	188,300,000	'	'
Commodity imbalances	74,300,000	80,500,000	'	'
Other current assets	70,700,000	62,700,000	'	'
Total current assets	1,440,800,000	1,443,800,000	'	'
Property, plant and equipment	'	'	'	'
Property, plant and equipment	11,951,500,000	10,755,000,000	'	'
Accumulated depreciation and amortization	1,837,100,000	1,652,600,000	'	'
Net property, plant and equipment	10,114,400,000	9,102,400,000	'	'
Investments and other assets	'	'	'	'
Investments in unconsolidated affiliates	738,900,000	825,600,000	'	'
Intercompany notes receivable	0	0	'	'
Goodwill and intangible assets	825,300,000	832,200,000	'	'
Other assets	22,100,000	22,400,000	'	'
Total investments and other assets	1,586,300,000	1,680,200,000	'	'
Total assets	13,141,500,000	12,226,400,000	'	'
Current liabilities	'	'	'	'
Current maturities of long-term debt	7,700,000	7,700,000	'	'
Accounts payable	1,216,100,000	1,255,400,000	'	'
Affiliate payables	29,400,000	47,500,000	'	'
Commodity imbalances	171,200,000	213,600,000	'	'
Accrued interest	0	0	'	'
Other current liabilities	136,000,000	89,100,000	'	'
Total current liabilities	1,560,400,000	1,613,300,000	'	'
Intercompany Debt	6,601,200,000	6,247,100,000	'	'
Long-term debt, excluding current maturities	53,800,000	59,600,000	'	'
Deferred credits and other liabilities	131,800,000	113,000,000	'	'
Commitments and contingencies	'	'	'	'
Equity	'	'	'	'
Equity excluding noncontrolling interests in consolidated subsidiaries	4,789,900,000	4,188,900,000	'	'
Noncontrolling interests in consolidated subsidiaries	4,400,000	4,500,000	'	'
Total equity	4,794,300,000	4,193,400,000	'	'
Total liabilities and equity	13,141,500,000	12,226,400,000	'	'
Consolidating Entries [member]	'	'	'	'
Current assets	'	'	'	'
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0	'	'
Affiliate receivables	0	0	'	'
Natural gas and natural gas liquids in storage	0	0	'	'
Commodity imbalances	0	0	'	'
Other current assets	0	0	'	'
Total current assets	0	0	'	'
Property, plant and equipment	'	'	'	'
Property, plant and equipment	0	0	'	'
Accumulated depreciation and amortization	0	0	'	'
Net property, plant and equipment	0	0	'	'
Investments and other assets	'	'	'	'
Investments in unconsolidated affiliates	-9,012,600,000	-8,525,300,000	'	'
Intercompany notes receivable	-14,213,200,000	-12,885,400,000	'	'
Goodwill and intangible assets	0	0	'	'
Other assets	0	0	'	'
Total investments and other assets	-23,225,800,000	-21,410,700,000	'	'
Total assets	-23,225,800,000	-21,410,700,000	'	'
Current liabilities	'	'	'	'
Current maturities of long-term debt	0	0	'	'
Accounts payable	0	0	'	'
Affiliate payables	0	0	'	'
Commodity imbalances	0	0	'	'
Accrued interest	0	0	'	'
Other current liabilities	0	0	'	'
Total current liabilities	0	0	'	'
Intercompany Debt	-14,213,200,000	-12,885,400,000	'	'
Long-term debt, excluding current maturities	0	0	'	'
Deferred credits and other liabilities	0	0	'	'
Commitments and contingencies	'	'	'	'
Equity	'	'	'	'
Equity excluding noncontrolling interests in consolidated subsidiaries	-9,012,600,000	-8,525,300,000	'	'
Noncontrolling interests in consolidated subsidiaries	0	0	'	'
Total equity	-9,012,600,000	-8,525,300,000	'	'
Total liabilities and equity	-23,225,800,000	-21,410,700,000	'	'
Total [Member]	'	'	'	'
Current assets	'	'	'	'
Cash and cash equivalents	54,000,000	134,500,000	723,000,000	537,100,000
Accounts receivable, net	951,600,000	1,103,100,000	'	'
Affiliate receivables	5,900,000	9,200,000	'	'
Natural gas and natural gas liquids in storage	338,300,000	188,300,000	'	'
Commodity imbalances	74,300,000	80,500,000	'	'
Other current assets	83,800,000	67,500,000	'	'
Total current assets	1,507,900,000	1,583,100,000	'	'
Property, plant and equipment	'	'	'	'
Property, plant and equipment	11,951,500,000	10,755,000,000	'	'
Accumulated depreciation and amortization	1,837,100,000	1,652,600,000	'	'
Net property, plant and equipment	10,114,400,000	9,102,400,000	'	'
Investments and other assets	'	'	'	'
Investments in unconsolidated affiliates	1,128,500,000	1,229,800,000	'	'
Intercompany notes receivable	0	0	'	'
Goodwill and intangible assets	825,300,000	832,200,000	'	'
Other assets	78,100,000	115,100,000	'	'
Total investments and other assets	2,031,900,000	2,177,100,000	'	'
Total assets	13,654,200,000	12,862,600,000	'	'
Current liabilities	'	'	'	'
Current maturities of long-term debt	7,700,000	7,700,000	'	'
Accounts payable	1,216,100,000	1,255,400,000	'	'
Affiliate payables	29,400,000	47,500,000	'	'
Commodity imbalances	171,200,000	213,600,000	'	'
Accrued interest	88,000,000	92,700,000	'	'
Other current liabilities	159,300,000	89,100,000	'	'
Total current liabilities	1,671,700,000	1,706,000,000	'	'
Intercompany Debt	0	0	'	'
Long-term debt, excluding current maturities	6,040,000,000	6,044,900,000	'	'
Deferred credits and other liabilities	131,800,000	113,000,000	'	'
Commitments and contingencies	'	'	'	'
Equity	'	'	'	'
Equity excluding noncontrolling interests in consolidated subsidiaries	5,806,300,000	4,994,200,000	'	'
Noncontrolling interests in consolidated subsidiaries	4,400,000	4,500,000	'	'
Total equity	5,810,700,000	4,998,700,000	'	'
Total liabilities and equity	$13,654,200,000	$12,862,600,000	'	'

SUPPLEMENTAL_CONDENSED_CONSOLI5

SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION, Cash Flows (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Operating activities	'	'	'	'
Cash provided by operating activities	'	'	$887,055,000	$654,118,000
Investing activities	'	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	-380,536,000	-449,072,000	-1,172,950,000	-1,373,904,000
Acquisition	'	'	-14,000,000	-304,889,000
Contributions to unconsolidated affiliates	'	'	-1,063,000	-4,558,000
Distributions received from unconsolidated affiliates	'	'	24,925,000	24,891,000
Proceeds from sale of assets	'	'	2,388,000	641,000
Cash provided by (used in) investing activities	'	'	-1,160,700,000	-1,657,819,000
Financing activities	'	'	'	'
Cash distributions: general and limited partners	'	'	-768,094,000	-669,981,000
Cash distributions: noncontrolling interests	'	'	-353,000	-442,000
Borrowing of notes payable, net	'	'	0	47,000,000
Proceeds from Issuance of Long-term Debt	'	'	0	1,247,822,000
Payments of Financing Costs	'	'	0	-10,217,000
Repayments of long-term debt	'	'	-5,738,000	-5,738,000
Issuance of common units, net of issuance costs	'	'	947,472,000	569,246,000
Contribution from general partner	'	'	19,857,000	11,967,000
Cash provided by (used in) financing activities	'	'	193,144,000	1,189,657,000
Change in cash and cash equivalents	'	'	-80,501,000	185,956,000
Cash and cash equivalents at beginning of period	'	'	134,530,000	537,074,000
Cash and cash equivalents at end of period	54,029,000	723,030,000	54,029,000	723,030,000
Parent [member]	'	'	'	'
Operating activities	'	'	'	'
Cash provided by operating activities	'	'	815,100,000	641,500,000
Investing activities	'	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	'	'	0	0
Acquisition	'	'	0	0
Contributions to unconsolidated affiliates	'	'	0	0
Distributions received from unconsolidated affiliates	'	'	0	0
Proceeds from sale of assets	'	'	0	0
Cash provided by (used in) investing activities	'	'	0	0
Financing activities	'	'	'	'
Cash distributions: general and limited partners	'	'	-768,100,000	-670,000,000
Cash distributions: noncontrolling interests	'	'	0	0
Borrowing of notes payable, net	'	'	0	47,000,000
Proceeds from Issuance of Long-term Debt	'	'	'	1,247,800,000
Payments of Financing Costs	'	'	'	-10,200,000
Intercompany borrowings (advances), net	'	'	-1,014,300,000	-1,837,200,000
Repayments of long-term debt	'	'	0	0
Issuance of common units, net of issuance costs	'	'	947,500,000	569,200,000
Contribution from general partner	'	'	19,800,000	11,900,000
Cash provided by (used in) financing activities	'	'	-815,100,000	-641,500,000
Change in cash and cash equivalents	'	'	0	0
Cash and cash equivalents at beginning of period	'	'	0	0
Cash and cash equivalents at end of period	0	0	0	0
Guarantor Subsidiary [member]	'	'	'	'
Operating activities	'	'	'	'
Cash provided by operating activities	'	'	53,700,000	48,100,000
Investing activities	'	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	'	'	0	0
Acquisition	'	'	0	0
Contributions to unconsolidated affiliates	'	'	0	0
Distributions received from unconsolidated affiliates	'	'	14,500,000	17,300,000
Proceeds from sale of assets	'	'	0	0
Cash provided by (used in) investing activities	'	'	14,500,000	17,300,000
Financing activities	'	'	'	'
Cash distributions: general and limited partners	'	'	-768,100,000	-670,000,000
Cash distributions: noncontrolling interests	'	'	0	0
Borrowing of notes payable, net	'	'	0	0
Proceeds from Issuance of Long-term Debt	'	'	'	0
Payments of Financing Costs	'	'	'	0
Intercompany borrowings (advances), net	'	'	619,400,000	790,500,000
Repayments of long-term debt	'	'	0	0
Issuance of common units, net of issuance costs	'	'	0	0
Contribution from general partner	'	'	0	0
Cash provided by (used in) financing activities	'	'	-148,700,000	120,500,000
Change in cash and cash equivalents	'	'	-80,500,000	185,900,000
Cash and cash equivalents at beginning of period	'	'	134,500,000	537,100,000
Cash and cash equivalents at end of period	54,000,000	723,000,000	54,000,000	723,000,000
Combined Non-Guarantor Subsidiaries [member]	'	'	'	'
Operating activities	'	'	'	'
Cash provided by operating activities	'	'	786,400,000	634,500,000
Investing activities	'	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	'	'	-1,173,000,000	-1,373,900,000
Acquisition	'	'	-14,000,000	-304,900,000
Contributions to unconsolidated affiliates	'	'	-1,000,000	-4,600,000
Distributions received from unconsolidated affiliates	'	'	10,400,000	7,600,000
Proceeds from sale of assets	'	'	2,400,000	700,000
Cash provided by (used in) investing activities	'	'	-1,175,200,000	-1,675,100,000
Financing activities	'	'	'	'
Cash distributions: general and limited partners	'	'	0	0
Cash distributions: noncontrolling interests	'	'	-400,000	-400,000
Borrowing of notes payable, net	'	'	0	0
Proceeds from Issuance of Long-term Debt	'	'	'	0
Payments of Financing Costs	'	'	'	0
Intercompany borrowings (advances), net	'	'	394,900,000	1,046,700,000
Repayments of long-term debt	'	'	-5,700,000	-5,700,000
Issuance of common units, net of issuance costs	'	'	0	0
Contribution from general partner	'	'	0	0
Cash provided by (used in) financing activities	'	'	388,800,000	1,040,600,000
Change in cash and cash equivalents	'	'	0	0
Cash and cash equivalents at beginning of period	'	'	0	0
Cash and cash equivalents at end of period	0	0	0	0
Consolidating Entries [member]	'	'	'	'
Operating activities	'	'	'	'
Cash provided by operating activities	'	'	-768,100,000	-670,000,000
Investing activities	'	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	'	'	0	0
Acquisition	'	'	0	0
Contributions to unconsolidated affiliates	'	'	0	0
Distributions received from unconsolidated affiliates	'	'	0	0
Proceeds from sale of assets	'	'	0	0
Cash provided by (used in) investing activities	'	'	0	0
Financing activities	'	'	'	'
Cash distributions: general and limited partners	'	'	768,100,000	670,000,000
Cash distributions: noncontrolling interests	'	'	0	0
Borrowing of notes payable, net	'	'	0	0
Proceeds from Issuance of Long-term Debt	'	'	'	0
Payments of Financing Costs	'	'	'	0
Intercompany borrowings (advances), net	'	'	0	0
Repayments of long-term debt	'	'	0	0
Issuance of common units, net of issuance costs	'	'	0	0
Contribution from general partner	'	'	0	0
Cash provided by (used in) financing activities	'	'	768,100,000	670,000,000
Change in cash and cash equivalents	'	'	0	0
Cash and cash equivalents at beginning of period	'	'	0	0
Cash and cash equivalents at end of period	0	0	0	0
Total [Member]	'	'	'	'
Operating activities	'	'	'	'
Cash provided by operating activities	'	'	887,100,000	654,100,000
Investing activities	'	'	'	'
Capital expenditures (less allowance for equity funds used during construction)	'	'	-1,173,000,000	-1,373,900,000
Acquisition	'	'	-14,000,000	-304,900,000
Contributions to unconsolidated affiliates	'	'	-1,000,000	-4,600,000
Distributions received from unconsolidated affiliates	'	'	24,900,000	24,900,000
Proceeds from sale of assets	'	'	2,400,000	700,000
Cash provided by (used in) investing activities	'	'	-1,160,700,000	-1,657,800,000
Financing activities	'	'	'	'
Cash distributions: general and limited partners	'	'	-768,100,000	-670,000,000
Cash distributions: noncontrolling interests	'	'	-400,000	-400,000
Borrowing of notes payable, net	'	'	0	47,000,000
Proceeds from Issuance of Long-term Debt	'	'	'	1,247,800,000
Payments of Financing Costs	'	'	'	-10,200,000
Intercompany borrowings (advances), net	'	'	0	0
Repayments of long-term debt	'	'	-5,700,000	-5,700,000
Issuance of common units, net of issuance costs	'	'	947,500,000	569,200,000
Contribution from general partner	'	'	19,800,000	11,900,000
Cash provided by (used in) financing activities	'	'	193,100,000	1,189,600,000
Change in cash and cash equivalents	'	'	-80,500,000	185,900,000
Cash and cash equivalents at beginning of period	'	'	134,500,000	537,100,000
Cash and cash equivalents at end of period	$54,000,000	$723,000,000	$54,000,000	$723,000,000