Targa Resources Partners (NGLS-PA) 10-Q 8 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	3 Months Ended
	Mar. 31, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	Targa Resources Partners LP
Trading Symbol	NGLS
Entity Central Index Key	0001379661
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Entity Small Business	false
Entity Emerging Growth Company	false

CONSOLIDATED BALANCE SHEETS (Un

CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 111.7	$ 203.3
Trade receivables, net of allowances of $0.2 and $0.1 million at March 31, 2019 and December 31, 2018	751.7	864.4
Inventories	197.9	164.7
Assets from risk management activities	75.9	115.3
Other current assets	24.9	32.2
Total current assets	1,162.1	1,379.9
Property, plant and equipment	18,182.3	17,213.8
Accumulated depreciation and amortization	(4,479.2)	(4,285.5)
Property, plant and equipment, net	13,703.1	12,928.3
Intangible assets, net	1,940.2	1,983.2
Goodwill, net	46.6	46.6
Long-term assets from risk management activities	23.1	34.1
Investments in unconsolidated affiliates	605.9	490.5
Other long-term assets	50	27.5
Total assets	17,531	16,890.1
Current liabilities:
Accounts payable and accrued liabilities	1,619.4	1,636.9
Accounts payable to Targa Resources Corp.	171.2	187.4
Liabilities from risk management activities	43.3	33.6
Current debt obligations	318.1	1,027.9
Total current liabilities	2,152	2,885.8
Long-term debt	6,683.5	5,197.4
Long-term liabilities from risk management activities	9.4	3.1
Deferred income taxes, net	23.9	23.9
Other long-term liabilities	258.3	233.8
Contingencies (see Note 16)
Owners' equity:
Series A preferred limited partners (5,000,000 and 5,000,000 units issued and 5,000,000 and 5,00,000 outstanding as of March 31, 2019 and December 31, 2018)	120.6	120.6
Common limited partners (275,168,410 and 275,168,410 units issued and 275,168,410 and 275,168,410 outstanding as of March 31, 2019 and December 31, 2018)	5,961	6,227.2
General partner (5,629,136 and 5,629,136 units issued and 5,629,136 and 5,629,136 outstanding as of March 31, 2019 and December 31, 2018)	797.1	802.6
Accumulated other comprehensive income (loss)	64.8	124.9
Partners' Capital	6,943.5	7,275.3
Noncontrolling interests	1,460.4	1,270.8
Total owners' equity	8,403.9	8,546.1
Total liabilities and owners' equity	$ 17,531	$ 16,890.1

CONSOLIDATED BALANCE SHEETS (_2

CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Trade receivables, allowances	$ 0.2	$ 0.1
Owners' equity:
Common limited partners units issued (in units)	275,168,410	275,168,410
Common limited partners units outstanding (in units)	275,168,410	275,168,410
General partner units issued (in units)	5,629,136	5,629,136
General partner units outstanding (in units)	5,629,136	5,629,136
Series A Preferred Limited Partner Units [Member]
Owners' equity:
Series A preferred limited partners units issued (in units)	5,000,000	5,000,000
Series A preferred limited partners units outstanding (in units)	5,000,000	5,000,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues:
Total revenues	$ 2,299.4	$ 2,455.6
Costs and expenses:
Product purchases	1,726	1,941
Operating expenses	190.2	173.2
Depreciation and amortization expense	237.4	198.1
General and administrative expense	77.7	52.6
Other operating (income) expense	3.4	0.3
Income (loss) from operations	64.7	90.4
Other income (expense):
Interest income (expense), net	(75.4)	20.2
Equity earnings (loss)	2.8	1.5
Gain (loss) from financing activities	(1.4)	0
Change in contingent considerations	(9.7)	(56.1)
Income (loss) before income taxes	(19)	56
Income tax (expense) benefit	0	0
Net income (loss)	(19)	56
Less: Net income (loss) attributable to noncontrolling interests	11.4	13.2
Net income (loss) attributable to Targa Resources Partners LP	(30.4)	42.8
Net income attributable to preferred limited partners	2.8	2.8
Net income (loss) attributable to general partner	(0.7)	0.8
Net income (loss) attributable to common limited partners	(32.5)	39.2
Net income (loss) attributable to Targa Resources Partners LP	(30.4)	42.8
Sales of Commodities [Member]
Revenues:
Total revenues	1,976.5	2,173.7
Fees from Midstream Services [Member]
Revenues:
Total revenues	$ 322.9	$ 281.9

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net income (loss)	$ (19)	$ 56
Other comprehensive income (loss):
Other comprehensive income (loss)	(60.1)	91.3
Comprehensive income (loss)	(79.1)	147.3
Less: Comprehensive income (loss) attributable to noncontrolling interests	11.4	13.2
Comprehensive income (loss) attributable to Targa Resources Partners LP	(90.5)	134.1
Commodity Contracts [Member]
Other comprehensive income (loss):
Change in fair value	(38.8)	64.6
Settlements reclassified to revenues	$ (21.3)	$ 26.7

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN OWNERS' EQUITY (Unaudited) - USD ($) $ in Millions	Total	Limited Partner Preferred [Member]	Limited Partners Common [Member]	General Partner Units [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Non-controlling Interests [Member]
Balance at Dec. 31, 2017	$ 7,858.2	$ 5,000	$ 275,168	$ 5,629	$ (46)	$ 475.1
Balance (in units) at Dec. 31, 2017		120,600	6,500,300	808,200
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contributions from Targa Resources Corp.	60	$ 0	$ 0	$ 0	0	0
Contributions from Targa Resources Corp. (in units)		0	58,800	1,200
Purchase of noncontrolling interests in subsidiary	1.2	$ 0	$ 0	$ 0	0	1.2
Distributions to noncontrolling interests	(16.5)	0	0	0	0	(16.5)
Contributions from noncontrolling interests	280.1	0	0	0	0	280.1
Other comprehensive income (loss)	91.3	0	0	0	91.3	0
Net income (loss)	56	0	0	0	0	13.2
Distributions	(228.5)	0	0	0	0	0
Balance at Mar. 31, 2018	8,101.8	$ 5,000	$ 275,168	$ 5,629	45.3	753.1
Balance (in units) at Mar. 31, 2018		120,600	6,377,100	805,700
Balance at Dec. 31, 2018	8,546.1	$ 120.6	$ 6,227.2	$ 802.6	124.9	1,270.8
Balance (in units) at Dec. 31, 2018		5,000,000	275,168,000	5,629,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Distributions to noncontrolling interests	(18.6)	$ 0	$ 0	$ 0	0	(18.6)
Contributions from noncontrolling interests	196.8	0	0	0	0	196.8
Other comprehensive income (loss)	(60.1)	0	0	0	(60.1)	0
Net income (loss)	(19)	2.8	(32.5)	(0.7)	0	11.4
Distributions	(241.3)	(2.8)	(233.7)	(4.8)	0	0
Balance at Mar. 31, 2019	$ 8,403.9	$ 120.6	$ 5,961	$ 797.1	$ 64.8	$ 1,460.4
Balance (in units) at Mar. 31, 2019		5,000,000	275,168,000	5,629,000

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net income (loss)	$ (19)	$ 56
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Amortization in interest expense	2.4	2.3
Depreciation and amortization expense	237.4	198.1
Accretion of asset retirement obligations	1	0.9
Increase (decrease) in redemption value of mandatorily redeemable preferred interests	0	(72.5)
Equity (earnings) loss of unconsolidated affiliates	(2.8)	(1.5)
Distributions of earnings received from unconsolidated affiliates	4.8	4.2
Risk management activities	7.2	10.9
(Gain) loss on sale or disposition of assets	3.2	(0.1)
(Gain) loss from financing activities	1.4	0
Change in contingent considerations	9.7	56.1
Changes in operating assets and liabilities, net of business acquisitions:
Receivables and other assets	83.9	114.2
Inventories	(60.6)	110.2
Accounts payable and other liabilities	39	(124.6)
Net cash provided by operating activities	307.6	354.2
Cash flows from investing activities
Outlays for property, plant and equipment	(942.9)	(595.9)
Proceeds from sale of assets	0.5	0
Investments in unconsolidated affiliates	(117.4)	(88)
Return of capital from unconsolidated affiliates	0	1.5
Other, net	(9)	5.1
Net cash used in investing activities	(1,068.8)	(677.3)
Debt obligations:
Proceeds from borrowings under credit facility	750	600
Repayments of credit facility	(780)	(240)
Proceeds from borrowings under accounts receivable securitization facility	378	0
Repayments of accounts receivable securitization facility	(350.4)	(50)
Proceeds from issuance of senior notes	1,500	0
Redemption of senior notes	(749.4)	0
Principal payments of finance leases	(2.7)	0
Costs incurred in connection with financing arrangements	(12.8)	0
Contributions from general partner	0	1.2
Contributions from TRC	0	58.8
Contributions from noncontrolling interests	196.8	280.1
Distributions to noncontrolling interests	(18.6)	(16.5)
Distributions to unitholders	(241.3)	(228.5)
Net cash provided by financing activities	669.6	405.1
Net change in cash and cash equivalents	(91.6)	82
Cash and cash equivalents, beginning of period	203.3	124.7
Cash and cash equivalents, end of period	$ 111.7	$ 206.7

Organization and Operations

Organization and Operations	3 Months Ended
	Mar. 31, 2019
Limited Liability Company Or Limited Partnership Business Organization And Operations [Abstract]
Organization and Operations	Our Organization Targa Resources Partners LP is a Delaware limited partnership formed in October 2006 by our parent, Targa Resources Corp. (“Targa” or “TRC” or the “Company” or “Parent”). In this Quarterly Report, unless the context requires otherwise, references to “we,” “us,” “our,” “TRP,” or the “Partnership” are intended to mean the business and operations of Targa Resources Partners LP and its consolidated subsidiaries. Our common units are wholly owned by TRC and no longer publicly traded as a result of TRC’s acquisition of our outstanding common units that it and its subsidiaries did not already own in 2016. The 5,000,000 9.00% Series A Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Units (the “Preferred Units”) that were issued in October 2015 remain outstanding as limited partner interests in us and continue to trade on the NYSE under the symbol “NGLS PRA.” Our Operations We are primarily engaged in the business of: • gathering, compressing, treating, processing, transporting and selling natural gas; • transporting, storing, fractionating, treating and selling NGLs and NGL products, including services to LPG exporters; and • gathering, storing, terminaling and selling crude oil. See Note 19 – Segment Information for certain financial information regarding our business segments. The employees supporting our operations are employed by Targa. Our consolidated financial statements include the direct costs of Targa employees deployed to our operating segments, as well as an allocation of costs associated with our usage of Targa’s centralized general and administrative services.

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	The accompanying unaudited consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and do not include all information and disclosures required by GAAP. Therefore, this information should be read in conjunction with our consolidated financial statements and notes contained in our Annual Report. The information furnished herein reflects all adjustments that are, in the opinion of management, necessary for a fair statement of the results of the interim periods reported. All significant intercompany balances and transactions have been eliminated in consolidation. Certain amounts in prior periods may have been reclassified to conform to the current year presentation. Operating results for the three months ended March 31, 2019, are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 .

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Significant Accounting Policies	The accounting policies that we follow are set forth in Note 3 – Significant Accounting Policies of the Notes to Consolidated Financial Statements in our Annual Report. Other than the updates noted below, there were no significant updates or revisions to our accounting policies during the three months ended March 31, 2019. Recent Accounting Pronouncements Recently adopted accounting pronouncements Leases In February 2016, the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) Leases (net of $0.4 million of lease incentives/deferred rent) • The package for transition relief, which among other things, allows us to carry forward the historical lease classification; • The land easements transition, which allows us to carry forward our historical accounting treatment for land easements prior to the effective date of the new leases standard and evaluate under Topic 842 only new or modified land easements on or after January 1, 2019; • The short-term lease election, which allows us to elect by all asset classes not to record on the balance sheet a lease whose initial term is twelve months or less; • The election to not separate non-lease components from lease components for all the asset classes in our current lease portfolio, where Targa is the lessee; and • The election to not separate non-lease components from lease components for gathering, processing and storage assets, where Targa is the lessor. Based on our election, we determined the non-lease component in certain of these arrangements is the predominant component, and therefore, account for the arrangements under ASC 606. We recognize the following for all leases (with the exception of short-term leases) at the commencement date: • A lease liability, which is a lessee’s obligation to make lease payments arising from a lease. • A right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. We determine if an arrangement is or contains a lease at inception. Leases with an initial term of twelve months or less are considered short-term leases, which are excluded from the balance sheet. Right-of-use assets and lease liabilities are recognized at the commencement date based on the present value of future lease payments over the lease term. The right-of-use asset also includes any lease prepayments and excludes lease incentives. As most of the Company’s leases do not provide an implicit interest rate, we use our incremental borrowing rate as the discount rate to compute the present value of our lease liability. The discount rate applied is determined based on information available on the date of adoption for all leases existing as of that date, and on the date of lease commencement for all subsequent leases. Our lease arrangements may include variable lease payments based on an index or market rate or may be based on performance. For variable lease payments based on an index or market rate, we estimate and apply a rate based on information available at the commencement date. Variable lease payments based on performance are excluded from the calculation of the right-of-use asset and lease liability, and are recognized in our Consolidated Statements of Operations when the contingency underlying such variable lease payments is resolved. Our lease terms may include options to extend or terminate the lease. Such options are included in the measurement of our right-of-use asset and liability, provided we determine that we are reasonably certain to exercise the option. See Note 11 – Leases for additional details. Recently issued accounting pronouncements not yet adopted Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract In August 2018, the FASB issued ASU Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract

Divestitures

Divestitures	3 Months Ended
	Mar. 31, 2019
Business Combinations [Abstract]
Divestitures	Note 4 — Subsequent Event Train 7 Joint Venture In February 2019, we announced an extension of Grand Prix from Southern Oklahoma to the STACK region of Central Oklahoma where it will connect with the Williams Companies, Inc. (“Williams”) Bluestem Pipeline and link the Conway, Kansas, and Mont Belvieu, Texas, NGL markets. In connection with this project, Williams has committed significant volumes to us that we will transport on Grand Prix and fractionate at our Mont Belvieu facilities. Williams also had an initial option to purchase a 20% equity interest in one of our recently announced 110 MBbl/d fractionation trains (Train 7 or Train 8) in Mont Belvieu. Williams exercised its option to acquire a 20% equity interest in Train 7 and subsequently executed a joint venture agreement with us in the second quarter of 2019. Certain fractionation-related infrastructure for Train 7, including storage caverns and brine handling, will be funded and owned 100% by Targa. Sale of Interest in Targa Badlands LLC On April 3, 2019, we closed on the sale of a 45% interest in Targa Badlands LLC, the entity that holds substantially all of our assets in North Dakota, to funds managed by GSO Capital Partners and Blackstone Tactical Opportunities (collectively, “Blackstone”) for $1.6 billion in cash. We used the net cash proceeds to repay debt and for general corporate purposes, including funding our growth capital program. We continue to be the operator of Targa Badlands LLC and hold majority governance rights. Future growth capital of Targa Badlands LLC is expected to be funded on a pro rata ownership basis. Targa Badlands LLC will pay a minimum quarterly distribution (“MQD”) to Blackstone and Targa, with Blackstone having a priority right on such MQDs. Additionally, Blackstone’s capital contributions would have a liquidation preference upon a sale of Targa Badlands LLC. We will continue to present Targa Badlands LLC on a consolidated basis in our consolidated financial statements.

Inventories

Inventories	3 Months Ended
	Mar. 31, 2019
Inventory Disclosure [Abstract]
Inventories	March 31, 2019 December 31, 2018 Commodities $ 176.4 $ 151.1 Materials and supplies 21.5 13.6 $ 197.9 $ 164.7

Property, Plant and Equipment a

Property, Plant and Equipment and Intangible Assets	3 Months Ended
	Mar. 31, 2019
Property Plant And Equipment And Intangible Assets [Abstract]
Property, Plant and Equipment and Intangible Assets	Note 6 — Property, Plant and Equipment and Intangible Assets March 31, 2019 December 31, 2018 Estimated Useful Lives (In Years) Gathering systems $ 8,417.2 $ 7,547.9 5 to 20 Processing and fractionation facilities 4,287.4 4,001.0 5 to 25 Terminaling and storage facilities 1,173.0 1,138.7 5 to 25 Transportation assets 1,016.8 445.1 10 to 25 Other property, plant and equipment 398.6 334.3 3 to 25 Land 149.2 144.3 — Construction in progress 2,699.2 3,602.5 — Finance lease right-of-use assets 40.9 — Property, plant and equipment 18,182.3 17,213.8 Accumulated depreciation and amortization (4,479.2 ) (4,285.5 ) Property, plant and equipment, net $ 13,703.1 $ 12,928.3 Intangible assets $ 2,736.6 $ 2,736.6 10 to 20 Accumulated amortization (796.4 ) (753.4 ) Intangible assets, net $ 1,940.2 $ 1,983.2 During the preparation of the Company's consolidated financial statements for the three months ended March 31, 2019, the Company identified an error related to depreciation expense on certain assets that should have been placed in-service during 2018. The Company does not believe this error is material to its previously issued historical consolidated financial statements for any of the periods impacted and accordingly, has not adjusted the historical financial statements. The Company has recorded the cumulative impact of the adjustment in the three months ended March 31, 2019. This adjustment resulted in a one-time $12.5 million overstatement of depreciation expense during the three months ended March 31, 2019. During the three months ended March 31, 2019 and 2018, depreciation expense was $194.4 million and $152.4 million. Intangible Assets Intangible assets consist of customer contracts and customer relationships acquired in prior business combinations. The fair value of these acquired intangible assets were determined at the date of acquisition based on the present values of estimated future cash flows. Amortization expense attributable to these assets is recorded over the periods in which we benefit from services provided to customers. We are amortizing these assets over lives ranging from 10 to 20 years The estimated annual amortization expense for intangible assets is approximately $171.6 million, $159.4 million, $149.5 million, $141.2 million and $136.0 million for each of the years 2019 through 2023. The changes in our intangible assets are as follows: Balance at December 31, 2018 $ 1,983.2 Amortization (43.0 ) Balance at March 31, 2019 $ 1,940.2

Investments in Unconsolidated A

Investments in Unconsolidated Affiliates	3 Months Ended
	Mar. 31, 2019
Equity Method Investments And Joint Ventures [Abstract]
Investments in Unconsolidated Affiliates	Our investments in unconsolidated affiliates consist of the following: • a • two non-operated joint ventures in South Texas: a 75% interest in T2 LaSalle Gathering Company L.L.C. (“T2 LaSalle”), a gas gathering company, and a 50% interest in T2 Eagle Ford Gathering Company L.L.C. (“T2 Eagle Ford”), a gas gathering company, (together the “T2 Joint Ventures”); • a 50% operated ownership interest in Cayenne Pipeline, LLC, a joint venture with American Midstream LLC that owns a 62-mile gas pipeline to an NGL pipeline, which connects the VESCO plant in Venice, Louisiana to the Enterprise Products Operating LLC (“Enterprise”) pipeline at Toca, Louisiana, for delivery to Enterprise’s Norco Fractionator (the “Cayenne Joint Venture”) ; • a 25% non-operated ownership interest in Gulf Coast Express Pipeline LLC (“GCX”) • a 50 • a 10% non-operated ownership interest in Delaware Basin Residue, LLC (the “Agua Blanca Joint Venture”) , a joint venture with affiliates of First Infrastructure Capital Advisors LLC and Markwest Energy Partners, L.P. in the Agua Blanca pipeline Investments in GCF, the Cayenne Joint Venture, GCX and the Agua Blanca Joint Venture are included in the total assets of our Logistics and Marketing segment. Investments in the T2 Joint Ventures and the Little Missouri 4 Joint Venture – The terms of these joint venture agreements do not afford us the degree of control required for consolidating them in our consolidated financial statements, but do afford us the significant influence required to employ the equity method of accounting The T2 Joint Ventures were formed to provide services for the benefit of their joint interest owners and have capacity lease agreements with their joint interest owners, which cover costs of operations (excluding depreciation and amortization). On April 1, 2019, we assumed the operatorship of the T2 Joint Ventures. The following table shows the activity related to our investments in unconsolidated affiliates: Balance at December 31, 2018 Equity Earnings (Loss) Cash Distributions Contributions Balance at March 31, 2019 GCF $ 40.3 $ 4.3 $ (2.2 ) $ — $ 42.4 T2 LaSalle (1) 49.3 (1.5 ) — — 47.8 T2 Eagle Ford (1) 99.0 (2.4 ) — — 96.6 Cayenne 16.6 1.9 (2.6 ) — 15.9 GCX (2) 211.6 0.6 — 110.4 322.6 Little Missouri 4 67.3 — — 7.0 74.3 Agua Blanca 6.4 (0.1 ) — — 6.3 Total $ 490.5 $ 2.8 $ (4.8 ) $ 117.4 $ 605.9 (1) As of March 31, 2019, $24.3 million of unamortized excess fair value over the T2 LaSalle and T2 Eagle Ford capital accounts remained. These basis differences, which are attributable to the underlying depreciable tangible gathering assets, are being amortized on a straight-line basis as components of equity earnings over the estimated 20-year useful lives of the underlying assets. (2) Our 25% interest in GCX is owned by Targa GCX Pipeline LLC (“GCX DevCo JV”), of which we own a 20% interest. GCX DevCo JV is accounted for on a consolidated basis in our consolidated financial statements.

Accounts Payable and Accrued Li

Accounts Payable and Accrued Liabilities	3 Months Ended
	Mar. 31, 2019
Payables And Accruals [Abstract]
Accounts Payable and Accrued Liabilities	March 31, 2019 December 31, 2018 Commodities $ 779.3 $ 721.9 Other goods and services 379.4 474.5 Interest 91.0 79.4 Permian Acquisition contingent consideration 317.9 308.2 Income and other taxes 40.4 45.4 Other 11.4 7.5 $ 1,619.4 $ 1,636.9 Accounts payable and accrued liabilities includes $28.9 million and $52.2 million of liabilities to creditors to whom we have issued checks that remained outstanding as of March 31, 2019 and December 31, 2018. Permian Acquisition Contingent Consideration As a result of a 2017 acquisition of certain gas gathering and processing and crude gathering assets in the Permian Basin (the “Permian Acquisition”), we have included the related contingent consideration in accounts payable and accrued liabilities as of March 31, 2019, and December 31, 2018. The Permian Acquisition contingent consideration represents the second earn-out payment, which will be paid in May 2019, and is derived on a multiple of realized gross margin during the earn-out period from contracts that existed on March 1, 2017, in accordance with the terms of the purchase and sale agreements. The first potential earn-out payment would have occurred in May 2018 and expired with no required payment. Changes in the value of the contingent consideration liability have been included in Other income (expense). For the period from December 31, 2018 to March 31, 2019, the value of the contingent consideration increased by $9.7 million, primarily attributable to the elimination of discounting and an increase in actual gross margin through the end of the earn-out period. During the three months ended March 31, 2018, we recognized $56.0 million of expense in Other income (expense) related to the change in fair value of the contingent consideration. See Note 14 – Fair Value Measurements for additional discussion of the fair value methodology.

Debt Obligations

Debt Obligations	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Debt Obligations	March 31, 2019 December 31, 2018 Current: Accounts receivable securitization facility, due December 2019 (1) $ 307.6 $ 280.0 Senior unsecured notes, 4⅛% fixed rate, due November 2019 — 749.4 307.6 1,029.4 Debt issuance costs, net of amortization — (1.5 ) Finance lease liabilities 10.5 — Current debt obligations 318.1 1,027.9 Long-term: Senior secured revolving credit facility, variable rate, due June 2023 (2) 670.0 700.0 Senior unsecured notes: 5¼% fixed rate, due May 2023 559.6 559.6 4¼% fixed rate, due November 2023 583.9 583.9 6¾% fixed rate, due March 2024 580.1 580.1 5⅛% fixed rate, due February 2025 500.0 500.0 5⅞% fixed rate, due April 2026 1,000.0 1,000.0 5⅜% fixed rate, due February 2027 500.0 500.0 6½% fixed rate, due July 2027 750.0 — 5% fixed rate, due January 2028 750.0 750.0 6⅞% fixed rate, due January 2029 750.0 — TPL notes, 4¾% fixed rate, due November 2021 (3) 6.5 6.5 TPL notes, 5⅞% fixed rate, due August 2023 (3) 48.1 48.1 Unamortized premium 0.3 0.3 6,698.5 5,228.5 Debt issuance costs, net of amortization (42.7 ) (31.1 ) Finance lease liabilities 27.7 — Long-term debt 6,683.5 5,197.4 Total debt obligations $ 7,001.6 $ 6,225.3 Irrevocable standby letters of credit outstanding (2) $ 69.8 $ 79.5 (1) As of March 31, 2019, we had $337.6 million of qualifying receivables under our $400.0 million accounts receivable securitization facility, resulting in availability of $30.0 million. (2) As of March 31, 2019, availability under our $2.2 billion senior secured revolving credit facility (“TRP Revolver”) was $1,460.2 million. (3) “TPL” refers to Targa Pipeline Partners LP. The following table shows the range of interest rates and weighted average interest rate incurred on our variable-rate debt obligations during the three months ended March 31, 2019: Range of Interest Rates Incurred Weighted Average Interest Rate Incurred TRP Revolver 3.8% - 4.3% 4.1% Accounts receivable securitization facility 3.4% 3.4% Compliance with Debt Covenants As of March 31, 2019, we were in compliance with the covenants contained in our various debt agreements. Senior Unsecured Notes Issuances In January 2019, we issued $750.0 million of 6½% Senior Notes due July 2027 and $750.0 million of 6 ⅞ Debt Extinguishment In February 2019, we redeemed in full our outstanding 4 ⅛

Other Long-term Liabilities

Other Long-term Liabilities	3 Months Ended
	Mar. 31, 2019
Other Liabilities Noncurrent [Abstract]
Other Long-term Liabilities	Other long-term liabilities are comprised of the following obligations: March 31, 2019 December 31, 2018 Asset retirement obligations $ 63.4 $ 55.0 Deferred revenue 174.6 175.5 Operating lease liabilities 17.3 — Other liabilities 3.0 3.3 Total long-term liabilities $ 258.3 $ 233.8 Asset Retirement Obligations Our asset retirement obligations (“ARO”) primarily relate to certain gas gathering pipelines, processing facilities and transportation assets. Deferred Revenue We have certain long-term contractual arrangements for which we have received consideration that we are not yet able to recognize as revenue. The resulting deferred revenue will be recognized once all conditions for revenue recognition have been met. Deferred revenue includes $129.0 million of payments received from Vitol Americas Corp. (“Vitol”) (formerly known as Noble Americas Corp.), a subsidiary of Vitol US Holding Co., in 2016, 2017, and 2018 as part of an agreement (the “Splitter Agreement”) related to the construction and operation of a crude oil and condensate splitter. In December 2018, Vitol elected to terminate the Splitter Agreement. The Splitter Agreement provides that the first three annual payments are ours if Vitol elects to terminate, which Vitol disputes. The timing of revenue recognition related to the Splitter Agreement deferred revenue is currently dependent upon resolution of the dispute with Vitol. Deferred revenue also includes nonmonetary consideration received in a 2015 amendment to a gas gathering and processing agreement and consideration received for other construction activities of facilities connected to our systems. The following table shows the changes in deferred revenue: Balance at December 31, 2018 $ 175.5 Additions — Revenue recognized (0.9 ) Balance at March 31, 2019 $ 174.6

Leases

Leases	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Leases	Note 11 – Leases We have non-cancellable operating leases primarily associated with our office facilities, rail assets, land, and storage and terminal assets. We have finance leases primarily associated with our tractors and vehicles. Our leases have remaining lease terms of 1 to 6 years, some of which include options to extend the lease term for up to 10 years. The balances of right-of-use assets and liabilities of finance leases and operating leases, and their locations on our Consolidated Balance Sheets are as follows: Balance Sheet Location March 31, 2019 Right-of-use assets Operating leases, gross Other long-term assets $ 25.2 Finance leases, gross Property, plant and equipment 40.9 Lease liabilities Current: Operating leases Accounts payable and accrued liabilities $ 6.6 Finance leases Current debt obligations 10.5 Non-current: Operating leases Other long-term liabilities 17.3 Finance leases Long-term debt 27.7 Operating lease costs and short-term lease costs are included in Operating expenses or General and administrative expense in our Consolidated Statements of Operations, depending on the nature of the leases. Finance lease costs are included in Depreciation and amortization expense and Interest income (expense) in our Consolidated Statements of Operations. The components of lease expense were as follows: Three Months Ended March 31, 2019 Lease cost Operating lease cost $ 1.9 Short-term lease cost 7.6 Variable lease cost 1.3 Finance lease cost Amortization of right-of-use assets 3.1 Interest expense 0.4 Total lease cost $ 14.3 Other supplemental information related to our leases are as follows: Three Months Ended March 31, 2019 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases $ 1.9 Operating cash flows for finance leases 0.4 Financing cash flows for finance leases 2.7 The weighted-average remaining lease terms for operating leases and finance leases are 4 years and 3 years, respectively. The weighted-average discount rates for operating leases and finance leases are 3.9% and 3.9%, respectively. The following table presents the maturities of our lease liabilities under non-cancellable leases as of March 31, 2019: Operating Leases Finance Leases Future Minimum Lease Payments Beginning After March 31, 2019 $ 7.4 $ 11.8 2020 5.6 11.0 2021 5.3 9.2 2022 4.2 8.2 2023 2.4 1.0 Thereafter 1.0 — Total undiscounted cash flows 25.9 41.2 Less imputed interest (2.0 ) (3.0 ) Total lease liabilities $ 23.9 $ 38.2 The following table presents future minimum payments under non-cancellable leases as of December 31, 2018: Leases 2019 $ 20.5 2020 17.7 2021 14.9 2022 12.6 2023 6.0 Thereafter 1.7 Total payments $ 73.4

Partnership Units and Related M

Partnership Units and Related Matters	3 Months Ended
	Mar. 31, 2019
Partners Capital [Abstract]
Partnership Units and Related Matters	Distributions TRC is entitled to receive all Partnership distributions after payment of preferred distributions each quarter. The following table details the distributions declared and paid by us for the three months ended March 31, 2019: Three Months Ended Date Paid Total Distributions Distributions to Targa Resources Corp. March 31, 2019 April 5, 2019 $ 437.8 $ 435.0 December 31, 2018 February 13, 2019 241.3 238.5 Contributions All capital contributions to us continue to be allocated 98% to the limited partner and 2% to our general partner; however, no units will be issued for those contributions. During the three months ended March 31, 2019, TRC did not make contributions to us. Preferred Units Our Preferred Units rank senior to our common units with respect to distribution rights. Distributions on our 5,000,000 Preferred Units are cumulative from the date of original issue in October 2015 and are payable monthly in arrears on the 15th day of each month of each year, when, as and if declared by the board of directors of our general partner. Distributions on our Preferred Units are payable out of amounts legally available at a rate equal to 9.0% per annum. On and after November 1, 2020, distributions on our Preferred Units will accumulate at an annual floating rate equal to the one-month LIBOR plus a spread of 7.71%. We paid $2.8 million of distributions to the holders of Preferred Units (“Preferred Unitholders”) for the three months ended March 31, 2019. Subsequent Event In April 2019, the board of directors of our general partner declared a cash distribution of $0.1875 per Preferred Unit, resulting in approximately $0.9 million in distributions that will be paid on May 15, 2019.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	3 Months Ended
	Mar. 31, 2019
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	The primary purpose of our commodity risk management activities is to manage our exposure to commodity price risk and reduce volatility in our operating cash flow due to fluctuations in commodity prices. We have entered into derivative instruments to hedge the commodity price risks associated with a portion of our expected (i) natural gas, NGL, and condensate equity volumes in our Gathering and Processing operations that result from percent-of-proceeds processing arrangements, (ii) future commodity purchases and sales in our Logistics and Marketing segment and (iii) natural gas transportation basis risk in our Logistics and Marketing segment. The hedge positions associated with (i) and (ii) above will move favorably in periods of falling commodity prices and unfavorably in periods of rising commodity prices and are designated as cash flow hedges for accounting purposes. The hedges generally match the NGL product composition and the NGL delivery points of our physical equity volumes. Our natural gas hedges are a mixture of specific gas delivery points and Henry Hub. The NGL hedges may be transacted as specific NGL hedges or as baskets of ethane, propane, normal butane, isobutane and natural gasoline based upon our expected equity NGL composition. We believe this approach avoids uncorrelated risks resulting from employing hedges on crude oil or other petroleum products as “proxy” hedges of NGL prices. Our natural gas and NGL hedges are settled using published index prices for delivery at various locations. We hedge a portion of our condensate equity volumes using crude oil hedges that are based on the NYMEX futures contracts for West Texas Intermediate light, sweet crude, which approximates the prices received for condensate. This exposes us to a market differential risk if the NYMEX futures do not move in exact parity with the sales price of our underlying condensate equity volumes. We also enter into derivative instruments to help manage other short-term commodity-related business risks. We have not designated these derivatives as hedges and record changes in fair value and cash settlements to revenues. At March 31, 2019, the notional volumes of our commodity derivative contracts were: Commodity Instrument Unit 2019 2020 2021 2022 2023 Natural Gas Swaps MMBtu/d 175,364 79,930 52,055 - - Natural Gas Basis Swaps MMBtu/d 111,100 189,119 166,658 150,000 95,000 NGL Swaps Bbl/d 17,903 13,267 3,676 - - NGL Futures Bbl/d 9,735 4,645 - - - NGL Options Bbl/d 410 - - - - Condensate Swaps Bbl/d 4,266 2,390 1,404 - - Condensate Options Bbl/d 590 - - - - Our derivative contracts are subject to netting arrangements that permit our contracting subsidiaries to net cash settle offsetting asset and liability positions with the same counterparty within the same Targa entity. We record derivative assets and liabilities on our Consolidated Balance Sheets on a gross basis, without considering the effect of master netting arrangements. The following schedules reflect the fair value of our derivative instruments and their location on our Consolidated Balance Sheets as well as pro forma reporting assuming that we reported derivatives subject to master netting agreements on a net basis: Fair Value as of March 31, 2019 Fair Value as of December 31, 2018 Balance Sheet Derivative Derivative Derivative Derivative Location Assets Liabilities Assets Liabilities Derivatives designated as hedging instruments Commodity contracts Current $ 72.5 $ 25.2 $ 112.5 $ 18.9 Long-term 20.4 3.1 31.6 1.5 Total derivatives designated as hedging instruments $ 92.9 $ 28.3 $ 144.1 $ 20.4 Derivatives not designated as hedging instruments Commodity contracts Current $ 3.4 $ 18.1 $ 2.8 $ 14.7 Long-term 2.7 6.3 2.5 1.6 Total derivatives not designated as hedging instruments $ 6.1 $ 24.4 $ 5.3 $ 16.3 Total current position $ 75.9 $ 43.3 $ 115.3 $ 33.6 Total long-term position 23.1 9.4 34.1 3.1 Total derivatives $ 99.0 $ 52.7 $ 149.4 $ 36.7 The pro forma impact of reporting derivatives on our Consolidated Balance Sheets on a net basis is as follows: Gross Presentation Pro Forma Net Presentation March 31, 2019 Asset Liability Collateral Asset Liability Current Position Counterparties with offsetting positions or collateral $ 69.0 $ (42.0 ) $ (7.3 ) $ 43.5 $ (23.8 ) Counterparties without offsetting positions - assets 6.9 - - 6.9 - Counterparties without offsetting positions - liabilities - (1.3 ) - - (1.3 ) 75.9 (43.3 ) (7.3 ) 50.4 (25.1 ) Long Term Position Counterparties with offsetting positions or collateral 19.0 (9.1 ) - 13.5 (3.6 ) Counterparties without offsetting positions - assets 4.1 - - 4.1 - Counterparties without offsetting positions - liabilities - (0.3 ) - - (0.3 ) 23.1 (9.4 ) - 17.6 (3.9 ) Total Derivatives Counterparties with offsetting positions or collateral 88.0 (51.1 ) (7.3 ) 57.0 (27.4 ) Counterparties without offsetting positions - assets 11.0 - - 11.0 - Counterparties without offsetting positions - liabilities - (1.6 ) - - (1.6 ) $ 99.0 $ (52.7 ) $ (7.3 ) $ 68.0 $ (29.0 ) Gross Presentation Pro Forma Net Presentation December 31, 2018 Asset Liability Collateral Asset Liability Current Position Counterparties with offsetting positions or collateral $ 100.0 $ (33.6 ) $ (14.2 ) $ 70.0 $ (17.8 ) Counterparties without offsetting positions - assets 15.3 - - 15.3 - Counterparties without offsetting positions - liabilities - - - - - 115.3 (33.6 ) (14.2 ) 85.3 (17.8 ) Long Term Position Counterparties with offsetting positions or collateral 8.9 (3.1 ) - 5.9 (0.1 ) Counterparties without offsetting positions - assets 25.2 - - 25.2 - Counterparties without offsetting positions - liabilities - - - - - 34.1 (3.1 ) - 31.1 (0.1 ) Total Derivatives Counterparties with offsetting positions or collateral 108.9 (36.7 ) (14.2 ) 75.9 (17.9 ) Counterparties without offsetting positions - assets 40.5 - - 40.5 - Counterparties without offsetting positions - liabilities - - - - - $ 149.4 $ (36.7 ) $ (14.2 ) $ 116.4 $ (17.9 ) Our payment obligations in connection with a majority of these hedging transactions are secured by a first priority lien in the collateral securing the TRP Revolver that ranks equal in right of payment with liens granted in favor of our senior secured lenders. Some of our hedges are futures contracts executed through a broker that clears the hedges through an exchange. We maintain a margin deposit with the broker in an amount sufficient enough to cover the fair value of our open futures positions. The margin deposit is considered collateral, which is located within other current assets on our Consolidated Balance Sheets and is not offset against the fair value of our derivative instruments. The fair value of our derivative instruments, depending on the type of instrument, was determined by the use of present value methods or standard option valuation models with assumptions about commodity prices based on those observed in underlying markets. The estimated fair value of our derivative instruments was a net asset of $46.3 million as of March 31, 2019. The estimated fair value is net of an adjustment for credit risk based on the default probabilities as indicated by market quotes for the counterparties’ credit default swap rates. The credit risk adjustment was immaterial for all periods presented. Our futures contracts that are cleared through an exchange are margined daily and do not require any credit adjustment. The following tables reflect amounts recorded in Other comprehensive income (“OCI”) and amounts reclassified from OCI to revenue for the periods indicated: Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Derivatives in Cash Flow Three Months Ended March 31, Hedging Relationships 2019 2018 Commodity contracts $ (38.8 ) $ 64.6 Gain (Loss) Reclassified from OCI into Income (Effective Portion) Three Months Ended March 31, Location of Gain (Loss) 2019 2018 Revenues $ 21.3 $ (26.7 ) Our consolidated earnings are also affected by the use of the mark-to-market method of accounting for derivative instruments that do not qualify for hedge accounting or that have not been designated as hedges. The changes in fair value of these instruments are recorded on the balance sheet and through earnings rather than being deferred until the anticipated transaction settles. The use of mark-to-market accounting for financial instruments can cause non-cash earnings volatility due to changes in the underlying commodity price indices. Location of Gain Gain (Loss) Recognized in Income on Derivatives Derivatives Not Designated Recognized in Income on Three Months Ended March 31, as Hedging Instruments Derivatives 2019 2018 Commodity contracts Revenue $ (9.5 ) $ (10.8 ) Based on valuations as of March 31, 2019, we expect to reclassify commodity hedge-related deferred gains of $64.6 million included in accumulated other comprehensive income into earnings before income taxes through the end of 2021, with $47.3 million of gains to be reclassified over the next twelve months. See Note 14 – Fair Value Measurements and Note 19 – Segment Information for additional disclosures related to derivative instruments and hedging activities.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Under GAAP, our Consolidated Balance Sheets reflect a mixture of measurement methods for financial assets and liabilities (“financial instruments”). Derivative financial instruments and contingent consideration related to business acquisitions are reported at fair value on our Consolidated Balance Sheets. Other financial instruments are reported at historical cost or amortized cost on our Consolidated Balance Sheets. The following are additional qualitative and quantitative disclosures regarding fair value measurements of financial instruments. Fair Value of Derivative Financial Instruments Our derivative instruments consist of financially settled commodity swaps, futures, option contracts and fixed-price forward commodity contracts with certain counterparties. We determine the fair value of our derivative contracts using present value methods or standard option valuation models with assumptions about commodity prices based on those observed in underlying markets. We have consistently applied these valuation techniques in all periods presented and we believe we have obtained the most accurate information available for the types of derivative contracts we hold. The fair values of our derivative instruments are sensitive to changes in forward pricing on natural gas, NGLs and crude oil. The financial position of these derivatives at March 31, 2019, a net asset position of $46.3 million, reflects the present value, adjusted for counterparty credit risk, of the amount we expect to receive or pay in the future on our derivative contracts. If forward pricing on natural gas, NGLs and crude oil were to increase by 10%, the result would be a fair value reflecting a net liability of $40.1 million, ignoring an adjustment for counterparty credit risk. If forward pricing on natural gas, NGLs and crude oil were to decrease by 10%, the result would be a fair value reflecting a net asset of $129.2 million, ignoring an adjustment for counterparty credit risk. Fair Value of Other Financial Instruments Due to their cash or near-cash nature, the carrying value of other financial instruments included in working capital (i.e., cash and cash equivalents, accounts receivable, accounts payable) approximates their fair value. Long-term debt is primarily the other financial instrument for which carrying value could vary significantly from fair value. We determined the supplemental fair value disclosures for our long-term debt as follows: • The TRP Revolver and the accounts receivable securitization facility are based on carrying value, which approximates fair value as their interest rates are based on prevailing market rates; and • Senior unsecured notes are based on quoted market prices derived from trades of the debt. Contingent consideration liabilities related to business acquisitions are carried at fair value until the end of the related earn-out period. Fair Value Hierarchy We categorize the inputs to the fair value measurements of financial assets and liabilities at each balance sheet reporting date using a three-tier fair value hierarchy that prioritizes the significant inputs used in measuring fair value: • Level 1 – observable inputs such as quoted prices in active markets; • Level 2 – inputs other than quoted prices in active markets that we can directly or indirectly observe to the extent that the markets are liquid for the relevant settlement periods; and • Level 3 – unobservable inputs in which little or no market data exists, therefore we must develop our own assumptions. The following table shows a breakdown by fair value hierarchy category for (1) financial instruments measurements included on our Consolidated Balance Sheets at fair value and (2) supplemental fair value disclosures for other financial instruments: March 31, 2019 Fair Value Carrying Value Total Level 1 Level 2 Level 3 Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value: Assets from commodity derivative contracts (1) $ 97.2 $ 97.2 $ — $ 93.3 $ 3.9 Liabilities from commodity derivative contracts (1) 50.9 50.9 — 50.5 0.4 TPL contingent consideration (2) 2.4 2.4 — — 2.4 Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value: Cash and cash equivalents 111.7 111.7 — — — TRP Revolver 670.0 670.0 — 670.0 — Senior unsecured notes 6,028.5 6,268.9 — 6,268.9 — Accounts receivable securitization facility 307.6 307.6 — 307.6 — December 31, 2018 Fair Value Carrying Value Total Level 1 Level 2 Level 3 Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value: Assets from commodity derivative contracts (1) $ 144.4 $ 144.4 $ — $ 137.5 $ 6.9 Liabilities from commodity derivative contracts (1) 31.7 31.7 — 31.3 0.4 Permian Acquisition contingent consideration (3) 308.2 308.2 — — 308.2 TPL contingent consideration (2) 2.4 2.4 — — 2.4 Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value: Cash and cash equivalents 203.3 203.3 — — — TRP Revolver 700.0 700.0 — 700.0 — Senior unsecured notes 5,277.9 5,088.9 — 5,088.9 — Accounts receivable securitization facility 280.0 280.0 — 280.0 — (1) The fair value of derivative contracts in this table is presented on a different basis than the Consolidated Balance Sheets presentation as disclosed in Note 13– Derivative Instruments and Hedging Activities. The above fair values reflect the total value of each derivative contract taken as a whole, whereas the Consolidated Balance Sheets presentation is based on the individual maturity dates of estimated future settlements. As such, an individual contract could have both an asset and liability position when segregated into its current and long-term portions for Consolidated Balance Sheets classification purposes. (2) We have a contingent consideration liability for TPL’s previous acquisition of a gas gathering system and related assets, which is carried at fair value. (3) We have a contingent consideration liability related to the Permian Acquisition, which was carried at fair value as of December 31, 2018. See Note 8 – Accounts Payable and Accrued Liabilities. Additional Information Regarding Level 3 Fair Value Measurements Included on Our Consolidated Balance Sheets We reported certain of our swaps and option contracts at fair value using Level 3 inputs due to such derivatives not having observable market prices or implied volatilities for substantially the full term of the derivative asset or liability. For valuations that include both observable and unobservable inputs, if the unobservable input is determined to be significant to the overall inputs, the entire valuation is categorized in Level 3. This includes derivatives valued using indicative price quotations whose contract length extends into unobservable periods. The fair value of these swaps is determined using a discounted cash flow valuation technique based on a forward commodity basis curve. For these derivatives, the primary input to the valuation model is the forward commodity basis curve, which is based on observable or public data sources and extrapolated when observable prices are not available. As of March 31, 2019, we had 13 commodity swap and option contracts categorized as Level 3. The significant unobservable inputs used in the fair value measurements of our Level 3 derivatives are (i) the forward natural gas liquids pricing curves, for which a significant portion of the derivative’s term is beyond available forward pricing and (ii) implied volatilities, which are unobservable as a result of inactive natural gas liquids options trading. The change in the fair value of Level 3 derivatives associated with a 10% change in the forward basis curve where prices are not observable is immaterial. The fair value of the Permian Acquisition contingent consideration as of December 31, 2018, was determined using a Monte Carlo simulation model. Significant inputs used in the fair value measurement include expected gross margin (calculated in accordance with the terms of the purchase and sale agreements), term of the earn-out period, risk adjusted discount rate and volatility associated with the underlying assets. The Permian Acquisition contingent consideration earn-out period ended on February 28, 2019. The first earn-out payment due in May 2018 expired with no required payment. The second earn-out payment will be paid in May 2019 and is derived on a multiple of realized gross margin during the earn-out period from contracts that existed on March 1, 2017, in accordance with the terms of the purchase and sale agreements. As such, the carrying value of the Permian Acquisition contingent consideration as of March 31, 2019, approximates fair value, as with our other accounts payables. See Note 8 – Accounts Payable and Accrued Liabilities for additional discussion of the Permian Acquisition contingent consideration. The fair value of the TPL contingent consideration was determined using a probability-based model measuring the likelihood of meeting certain volumetric measures. The inputs for both models are not observable; therefore, the entire valuations of the contingent considerations are categorized in Level 3. Changes in the fair value of these liabilities are included in Other income (expense) in our Consolidated Statements of Operations. The following table summarizes the changes in fair value of our financial instruments classified as Level 3 in the fair value hierarchy: Commodity Derivative Contracts Contingent Asset/(Liability) Consideration Balance, December 31, 2018 $ 6.5 $ (310.6 ) Completion of Permian Acquisition contingent consideration earn-out period - 308.2 Unrealized gain/(loss) included in OCI (3.1 ) - Balance, March 31, 2019 $ 3.4 $ (2.4 )

Related Party Transactions - Ta

Related Party Transactions - Targa	3 Months Ended
	Mar. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions - Targa	Relationship with Targa We do not have any employees. Targa provides operational, general and administrative and other services to us associated with our existing assets and assets acquired from third parties. Targa performs centralized corporate functions for us, such as legal, accounting, treasury, insurance, risk management, health, safety and environmental, information technology, human resources, credit, payroll, internal audit, taxes, engineering and marketing. Our Partnership Agreement governs the reimbursement of costs incurred by Targa on behalf of us. Targa charges us for all the direct costs of the employees assigned to our operations, as well as all general and administrative support costs other than (1) costs attributable to Targa’s status as a separate reporting company and (2) until March 2018, costs of Targa providing management and support services to certain unaffiliated spun-off entities. We generally reimburse Targa monthly for cost allocations to the extent that Targa has made a cash outlay. The following table summarizes transactions with Targa. Management believes these transactions are executed on terms that are fair and reasonable: Three Months Ended March 31, 2019 2018 Targa billings of payroll and related costs included in operating expenses $ 54.1 $ 59.5 Targa allocation of general and administrative expense 67.8 47.3 Cash distributions to Targa based on general partner and limited partner ownership 238.5 225.7 Cash contributions from Targa related to limited partner ownership (1) — 58.8 Cash contributions from Targa to maintain its 2% general partner ownership — 1.2 __________________________________________________________________________________________________________ (1) The cash contributions from Targa related to limited partner ownership were allocated 98% to the limited partner and 2% to general partner. See Note 12 – Partnership Units and Related Matters.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2019
Loss Contingency [Abstract]
Contingencies	Legal Proceedings We are a party to various legal, administrative and regulatory proceedings that have arisen in the ordinary course of our business. We are also a party to various proceedings with governmental environmental agencies in 2019, including but not limited to the Environmental Protection Agency, Texas Commission on Environmental Quality, Oklahoma Department of Environmental Quality, New Mexico Environment Department, Louisiana Department of Environmental Quality and North Dakota Department of Environmental Quality, which assert penalties for alleged violations of environmental regulations, including air emissions, discharges into the environment and reporting deficiencies, related to events that have arisen at certain of our facilities in the ordinary course of our business. On February 26, 2019, the U.S. Environmental Protection Agency Region 8 and Targa Badlands LLC entered into a Final Order and Consent Agreement in connection with Targa Badlands LLC’s alleged violation of Subpart ZZZZ of the National Emission Standards for Hazardous Air Pollutants at its Junction Compressor Station in McKenzie County, North Dakota. The Consent Agreement imposed a $220,000 civil penalty and requires certain compliance improvements.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2019
Revenue From Contract With Customer [Abstract]
Revenue	Note 17 – Revenue Fixed consideration allocated to remaining performance obligations The following table includes the estimated minimum revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) at the end of the reporting period and is comprised of fixed consideration primarily attributable to contracts with minimum volume commitments and for which a guaranteed amount of revenue can be calculated . These contracts are comprised primarily of gathering and processing, fractionation, export, terminaling and storage agreements. 2019 2020 2021 and after Fixed consideration to be recognized as of March 31, 2019 $ 394.3 $ 463.0 $ 3,327.5 In accordance with the optional exemptions that we elected to apply, the amounts presented in the table above exclude variable consideration for which the allocation exception is met and consideration associated with performance obligations of short-term contracts. In addition, consideration from contracts for which we recognize revenue at the amount that we have the right to invoice for services performed is also excluded from the table above, with the exception of any fixed consideration attributable to such contracts. The nature of the performance obligations for which the consideration has been excluded is consistent with the performance obligations described within our revenue recognition accounting policy; the estimated remaining duration of such contracts primarily ranges from 1 to 20 years. In addition, variability exists in the consideration excluded due to the unknown quantity and composition of volumes to be serviced or sold as well as fluctuations in the market price of commodities to be received as consideration or sold over the applicable remaining contract terms. Such variability is resolved at the end of each future month or quarter. For disclosures related to disaggregated revenue, see Note 19 – Segment Information.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	3 Months Ended
	Mar. 31, 2019
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Three Months Ended March 31, 2019 2018 Cash: Interest paid, net of capitalized interest (1) $ 61.2 $ 39.4 Income taxes paid, net of refunds 0.3 0.2 Non-cash investing activities: Deadstock commodity inventory transferred to property, plant and equipment $ 17.5 $ 1.7 Impact of capital expenditure accruals on property, plant and equipment (38.4 ) (22.3 ) Transfers from materials and supplies inventory to property, plant and equipment 1.1 0.4 Contribution of property, plant and equipment to investments in unconsolidated affiliates — 16.0 Change in ARO liability and property, plant and equipment 7.4 2.1 Non-cash balance sheet movements related to acquisition of related party: Intercompany payable $ — $ 1.4 Noncontrolling interest — 1.2 Lease liabilities arising from recognition of right-of-use assets: Operating lease $ 0.4 $ — Finance lease 1.5 — __________________ (1) Interest capitalized on major projects was $18.9 million and $9.6 million for the three months ended March 31, 2019 and 2018.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Segment Information	We operate in two primary segments: (i) Gathering and Processing, and (ii) Logistics and Marketing (also referred to as the Downstream Business). Our reportable segments include operating segments that have been aggregated based on the nature of the products and services provided. Our Gathering and Processing segment includes assets used in the gathering of natural gas produced from oil and gas wells and processing this raw natural gas into merchantable natural gas by extracting NGLs and removing impurities; and assets used for crude oil gathering and terminaling. The Gathering and Processing segment's assets are located in the Permian Basin of West Texas and Southeast New Mexico (including the Midland and Delaware Basins); the Eagle Ford Shale in South Texas; the Barnett Shale in North Texas; the Anadarko, Ardmore, and Arkoma Basins in Oklahoma (including the SCOOP and STACK) and South Central Kansas; the Williston Basin in North Dakota; and the onshore and near offshore regions of the Louisiana Gulf Coast and the Gulf of Mexico. Our Logistics and Marketing segment includes the activities and assets necessary to convert mixed NGLs into NGL products and also includes other assets and value-added services such as storing, fractionating, terminaling, transporting and marketing of NGLs and NGL products, including services to LPG exporters; storing and terminaling of refined petroleum products and crude oil and certain natural gas supply and marketing activities in support of our other businesses. The Logistics and Marketing segment includes the Grand Prix pipeline, which is currently under construction with certain segments of the pipeline currently in operation. The associated assets are generally connected to and supplied in part by our Gathering and Processing segment and, except for the pipeline projects and smaller terminals, are located predominantly in Mont Belvieu and Galena Park, Texas, and in Lake Charles, Louisiana. Other contains the results of commodity derivative activities related to Gathering and Processing hedges of equity volumes that are included in operating margin and mark-to-market gains/losses related to derivative contracts that were not designated as cash flow hedges. Elimination of inter-segment transactions are reflected in the corporate and eliminations column. Reportable segment information is shown in the following tables: Three Months Ended March 31, 2019 Gathering and Processing Logistics and Marketing Other Corporate and Eliminations Total Revenues Sales of commodities $ 247.6 $ 1,726.8 $ 2.1 $ — $ 1,976.5 Fees from midstream services 199.9 123.0 — — 322.9 447.5 1,849.8 2.1 — 2,299.4 Intersegment revenues Sales of commodities 822.8 38.4 — (861.2 ) — Fees from midstream services 1.9 5.5 — (7.4 ) — 824.7 43.9 — (868.6 ) — Revenues $ 1,272.2 $ 1,893.7 $ 2.1 $ (868.6 ) $ 2,299.4 Operating margin $ 229.0 $ 152.1 $ 2.1 $ — $ 383.2 Other financial information: Total assets (1) $ 11,713.9 $ 5,644.9 $ 87.9 $ 84.3 $ 17,531.0 Goodwill $ 46.6 $ — $ — $ — $ 46.6 Capital expenditures $ 417.8 $ 470.9 $ — $ 16.9 $ 905.6 __________________________________________________________________________________________ (1) Assets in the Corporate and Eliminations column primarily include cash, prepaids and debt issuance costs for our TRP Revolver. Three Months Ended March 31, 2018 Gathering and Processing Logistics and Marketing Other Corporate and Eliminations Total Revenues Sales of commodities $ 265.2 $ 1,926.3 $ (17.8 ) $ — $ 2,173.7 Fees from midstream services 161.3 120.6 — — 281.9 426.5 2,046.9 (17.8 ) — 2,455.6 Intersegment revenues Sales of commodities 866.5 55.7 — (922.2 ) — Fees from midstream services 1.9 6.9 — (8.8 ) — 868.4 62.6 — (931.0 ) — Revenues $ 1,294.9 $ 2,109.5 $ (17.8 ) $ (931.0 ) $ 2,455.6 Operating margin $ 220.8 $ 138.4 $ (17.8 ) $ — $ 341.4 Other financial information: Total assets (1) $ 10,908.5 $ 3,595.1 $ 103.0 $ 121.1 $ 14,727.7 Goodwill $ 256.6 $ — $ — $ — $ 256.6 Capital expenditures $ 273.2 $ 251.0 $ — $ 33.8 $ 558.0 ____________________________________________________________________________________________ (1) Assets in the Corporate and Eliminations column primarily include cash, prepaids and debt issuance costs for our TRP Revolver. The following table shows our consolidated revenues disaggregated by product and service for the periods presented: Three Months Ended March 31, 2019 2018 Sales of commodities: Revenue recognized from contracts with customers: Natural gas $ 411.3 $ 470.1 NGL 1,408.1 1,607.3 Condensate and crude oil 137.7 86.9 Petroleum products 7.6 48.2 1,964.7 2,212.5 Non-customer revenue: Derivative activities - Hedge 21.3 (28.0 ) Derivative activities - Non-hedge (1) (9.5 ) (10.8 ) 11.8 (38.8 ) Total sales of commodities 1,976.5 2,173.7 Fees from midstream services: Revenue recognized from contracts with customers: NGL transportation and services 36.2 41.1 Storage, terminaling and export 79.6 78.2 Gathering and processing 194.5 152.1 Other 12.6 10.5 Total fees from midstream services 322.9 281.9 Total revenues $ 2,299.4 $ 2,455.6 __________________________________________________________________________________________ (1) Represents derivative activities that are not designated as hedging instruments under ASC 815. The following table shows a reconciliation of reportable segment operating margin to income (loss) before income taxes for the periods presented: Three Months Ended March 31, 2019 2018 Reconciliation of reportable segment operating margin to income (loss) before income taxes: Gathering and Processing operating margin $ 229.0 $ 220.8 Logistics and Marketing operating margin 152.1 138.4 Other operating margin 2.1 (17.8 ) Depreciation and amortization expense (237.4 ) (198.1 ) General and administrative expense (77.7 ) (52.6 ) Interest income (expense), net (75.4 ) 20.2 Change in contingent considerations (9.7 ) (56.1 ) Other, net (2.0 ) 1.2 Income (loss) before income taxes $ (19.0 ) $ 56.0

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently adopted accounting pronouncements Leases In February 2016, the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) Leases (net of $0.4 million of lease incentives/deferred rent) • The package for transition relief, which among other things, allows us to carry forward the historical lease classification; • The land easements transition, which allows us to carry forward our historical accounting treatment for land easements prior to the effective date of the new leases standard and evaluate under Topic 842 only new or modified land easements on or after January 1, 2019; • The short-term lease election, which allows us to elect by all asset classes not to record on the balance sheet a lease whose initial term is twelve months or less; • The election to not separate non-lease components from lease components for all the asset classes in our current lease portfolio, where Targa is the lessee; and • The election to not separate non-lease components from lease components for gathering, processing and storage assets, where Targa is the lessor. Based on our election, we determined the non-lease component in certain of these arrangements is the predominant component, and therefore, account for the arrangements under ASC 606. We recognize the following for all leases (with the exception of short-term leases) at the commencement date: • A lease liability, which is a lessee’s obligation to make lease payments arising from a lease. • A right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. We determine if an arrangement is or contains a lease at inception. Leases with an initial term of twelve months or less are considered short-term leases, which are excluded from the balance sheet. Right-of-use assets and lease liabilities are recognized at the commencement date based on the present value of future lease payments over the lease term. The right-of-use asset also includes any lease prepayments and excludes lease incentives. As most of the Company’s leases do not provide an implicit interest rate, we use our incremental borrowing rate as the discount rate to compute the present value of our lease liability. The discount rate applied is determined based on information available on the date of adoption for all leases existing as of that date, and on the date of lease commencement for all subsequent leases. Our lease arrangements may include variable lease payments based on an index or market rate or may be based on performance. For variable lease payments based on an index or market rate, we estimate and apply a rate based on information available at the commencement date. Variable lease payments based on performance are excluded from the calculation of the right-of-use asset and lease liability, and are recognized in our Consolidated Statements of Operations when the contingency underlying such variable lease payments is resolved. Our lease terms may include options to extend or terminate the lease. Such options are included in the measurement of our right-of-use asset and liability, provided we determine that we are reasonably certain to exercise the option. Recently issued accounting pronouncements not yet adopted Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract In August 2018, the FASB issued ASU Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2019
Inventory Disclosure [Abstract]
Components of Inventories	March 31, 2019 December 31, 2018 Commodities $ 176.4 $ 151.1 Materials and supplies 21.5 13.6 $ 197.9 $ 164.7

Property, Plant and Equipment_2

Property, Plant and Equipment and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2019
Property Plant And Equipment And Intangible Assets [Abstract]
Property, Plant and Equipment and Intangible Assets	March 31, 2019 December 31, 2018 Estimated Useful Lives (In Years) Gathering systems $ 8,417.2 $ 7,547.9 5 to 20 Processing and fractionation facilities 4,287.4 4,001.0 5 to 25 Terminaling and storage facilities 1,173.0 1,138.7 5 to 25 Transportation assets 1,016.8 445.1 10 to 25 Other property, plant and equipment 398.6 334.3 3 to 25 Land 149.2 144.3 — Construction in progress 2,699.2 3,602.5 — Finance lease right-of-use assets 40.9 — Property, plant and equipment 18,182.3 17,213.8 Accumulated depreciation and amortization (4,479.2 ) (4,285.5 ) Property, plant and equipment, net $ 13,703.1 $ 12,928.3 Intangible assets $ 2,736.6 $ 2,736.6 10 to 20 Accumulated amortization (796.4 ) (753.4 ) Intangible assets, net $ 1,940.2 $ 1,983.2
Schedule of Changes in Intangible Assets	The changes in our intangible assets are as follows: Balance at December 31, 2018 $ 1,983.2 Amortization (43.0 ) Balance at March 31, 2019 $ 1,940.2

Investments in Unconsolidated_2

Investments in Unconsolidated Affiliates (Tables)	3 Months Ended
	Mar. 31, 2019
Equity Method Investments And Joint Ventures [Abstract]
Activity Related to Investment in Unconsolidated Affiliate	The following table shows the activity related to our investments in unconsolidated affiliates: Balance at December 31, 2018 Equity Earnings (Loss) Cash Distributions Contributions Balance at March 31, 2019 GCF $ 40.3 $ 4.3 $ (2.2 ) $ — $ 42.4 T2 LaSalle (1) 49.3 (1.5 ) — — 47.8 T2 Eagle Ford (1) 99.0 (2.4 ) — — 96.6 Cayenne 16.6 1.9 (2.6 ) — 15.9 GCX (2) 211.6 0.6 — 110.4 322.6 Little Missouri 4 67.3 — — 7.0 74.3 Agua Blanca 6.4 (0.1 ) — — 6.3 Total $ 490.5 $ 2.8 $ (4.8 ) $ 117.4 $ 605.9 (1) As of March 31, 2019, $24.3 million of unamortized excess fair value over the T2 LaSalle and T2 Eagle Ford capital accounts remained. These basis differences, which are attributable to the underlying depreciable tangible gathering assets, are being amortized on a straight-line basis as components of equity earnings over the estimated 20-year useful lives of the underlying assets. (2) Our 25% interest in GCX is owned by Targa GCX Pipeline LLC (“GCX DevCo JV”), of which we own a 20% interest. GCX DevCo JV is accounted for on a consolidated basis in our consolidated financial statements.

Accounts Payable and Accrued _2

Accounts Payable and Accrued Liabilities (Tables)	3 Months Ended
	Mar. 31, 2019
Payables And Accruals [Abstract]
Schedule of Accounts Payable and Accrued Liabilities	March 31, 2019 December 31, 2018 Commodities $ 779.3 $ 721.9 Other goods and services 379.4 474.5 Interest 91.0 79.4 Permian Acquisition contingent consideration 317.9 308.2 Income and other taxes 40.4 45.4 Other 11.4 7.5 $ 1,619.4 $ 1,636.9

Debt Obligations (Tables)

Debt Obligations (Tables)	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Schedule of Outstanding Debt	March 31, 2019 December 31, 2018 Current: Accounts receivable securitization facility, due December 2019 (1) $ 307.6 $ 280.0 Senior unsecured notes, 4⅛% fixed rate, due November 2019 — 749.4 307.6 1,029.4 Debt issuance costs, net of amortization — (1.5 ) Finance lease liabilities 10.5 — Current debt obligations 318.1 1,027.9 Long-term: Senior secured revolving credit facility, variable rate, due June 2023 (2) 670.0 700.0 Senior unsecured notes: 5¼% fixed rate, due May 2023 559.6 559.6 4¼% fixed rate, due November 2023 583.9 583.9 6¾% fixed rate, due March 2024 580.1 580.1 5⅛% fixed rate, due February 2025 500.0 500.0 5⅞% fixed rate, due April 2026 1,000.0 1,000.0 5⅜% fixed rate, due February 2027 500.0 500.0 6½% fixed rate, due July 2027 750.0 — 5% fixed rate, due January 2028 750.0 750.0 6⅞% fixed rate, due January 2029 750.0 — TPL notes, 4¾% fixed rate, due November 2021 (3) 6.5 6.5 TPL notes, 5⅞% fixed rate, due August 2023 (3) 48.1 48.1 Unamortized premium 0.3 0.3 6,698.5 5,228.5 Debt issuance costs, net of amortization (42.7 ) (31.1 ) Finance lease liabilities 27.7 — Long-term debt 6,683.5 5,197.4 Total debt obligations $ 7,001.6 $ 6,225.3 Irrevocable standby letters of credit outstanding (2) $ 69.8 $ 79.5 (1) As of March 31, 2019, we had $337.6 million of qualifying receivables under our $400.0 million accounts receivable securitization facility, resulting in availability of $30.0 million. (2) As of March 31, 2019, availability under our $2.2 billion senior secured revolving credit facility (“TRP Revolver”) was $1,460.2 million. (3) “TPL” refers to Targa Pipeline Partners LP.
Interest Rates Incurred on Variable-Rate Debt Obligations	The following table shows the range of interest rates and weighted average interest rate incurred on our variable-rate debt obligations during the three months ended March 31, 2019: Range of Interest Rates Incurred Weighted Average Interest Rate Incurred TRP Revolver 3.8% - 4.3% 4.1% Accounts receivable securitization facility 3.4% 3.4%

Other Long-term Liabilities (Ta

Other Long-term Liabilities (Tables)	3 Months Ended
	Mar. 31, 2019
Other Liabilities Noncurrent [Abstract]
Other Long-term Liabilities	Other long-term liabilities are comprised of the following obligations: March 31, 2019 December 31, 2018 Asset retirement obligations $ 63.4 $ 55.0 Deferred revenue 174.6 175.5 Operating lease liabilities 17.3 — Other liabilities 3.0 3.3 Total long-term liabilities $ 258.3 $ 233.8
Changes in Deferred Revenue	The following table shows the changes in deferred revenue: Balance at December 31, 2018 $ 175.5 Additions — Revenue recognized (0.9 ) Balance at March 31, 2019 $ 174.6

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Summary of Balances of Right-of-Use Assets and Liabilities of Finance and Operating Leases	The balances of right-of-use assets and liabilities of finance leases and operating leases, and their locations on our Consolidated Balance Sheets are as follows: Balance Sheet Location March 31, 2019 Right-of-use assets Operating leases, gross Other long-term assets $ 25.2 Finance leases, gross Property, plant and equipment 40.9 Lease liabilities Current: Operating leases Accounts payable and accrued liabilities $ 6.6 Finance leases Current debt obligations 10.5 Non-current: Operating leases Other long-term liabilities 17.3 Finance leases Long-term debt 27.7
Components of Lease Expense	Operating lease costs and short-term lease costs are included in Operating expenses or General and administrative expense in our Consolidated Statements of Operations, depending on the nature of the leases. Finance lease costs are included in Depreciation and amortization expense and Interest income (expense) in our Consolidated Statements of Operations. The components of lease expense were as follows: Three Months Ended March 31, 2019 Lease cost Operating lease cost $ 1.9 Short-term lease cost 7.6 Variable lease cost 1.3 Finance lease cost Amortization of right-of-use assets 3.1 Interest expense 0.4 Total lease cost $ 14.3
Summary of Other Supplemental Information Related to Leases	Other supplemental information related to our leases are as follows: Three Months Ended March 31, 2019 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases $ 1.9 Operating cash flows for finance leases 0.4 Financing cash flows for finance leases 2.7
Summary of Maturities of Lease Liabilities under Non-cancellable Leases	The following table presents the maturities of our lease liabilities under non-cancellable leases as of March 31, 2019: Operating Leases Finance Leases Future Minimum Lease Payments Beginning After March 31, 2019 $ 7.4 $ 11.8 2020 5.6 11.0 2021 5.3 9.2 2022 4.2 8.2 2023 2.4 1.0 Thereafter 1.0 — Total undiscounted cash flows 25.9 41.2 Less imputed interest (2.0 ) (3.0 ) Total lease liabilities $ 23.9 $ 38.2
Summary of Future Minimum Payments under Non-cancellable Leases	The following table presents future minimum payments under non-cancellable leases as of December 31, 2018: Leases 2019 $ 20.5 2020 17.7 2021 14.9 2022 12.6 2023 6.0 Thereafter 1.7 Total payments $ 73.4

Partnership Units and Related_2

Partnership Units and Related Matters (Tables)	3 Months Ended
	Mar. 31, 2019
Partners Capital [Abstract]
Schedule of Distributions	The following table details the distributions declared and paid by us for the three months ended March 31, 2019: Three Months Ended Date Paid Total Distributions Distributions to Targa Resources Corp. March 31, 2019 April 5, 2019 $ 437.8 $ 435.0 December 31, 2018 February 13, 2019 241.3 238.5

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2019
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Notional Volume of Commodity Hedges	At March 31, 2019, the notional volumes of our commodity derivative contracts were: Commodity Instrument Unit 2019 2020 2021 2022 2023 Natural Gas Swaps MMBtu/d 175,364 79,930 52,055 - - Natural Gas Basis Swaps MMBtu/d 111,100 189,119 166,658 150,000 95,000 NGL Swaps Bbl/d 17,903 13,267 3,676 - - NGL Futures Bbl/d 9,735 4,645 - - - NGL Options Bbl/d 410 - - - - Condensate Swaps Bbl/d 4,266 2,390 1,404 - - Condensate Options Bbl/d 590 - - - -
Fair Values of Derivative Instruments	The following schedules reflect the fair value of our derivative instruments and their location on our Consolidated Balance Sheets as well as pro forma reporting assuming that we reported derivatives subject to master netting agreements on a net basis: Fair Value as of March 31, 2019 Fair Value as of December 31, 2018 Balance Sheet Derivative Derivative Derivative Derivative Location Assets Liabilities Assets Liabilities Derivatives designated as hedging instruments Commodity contracts Current $ 72.5 $ 25.2 $ 112.5 $ 18.9 Long-term 20.4 3.1 31.6 1.5 Total derivatives designated as hedging instruments $ 92.9 $ 28.3 $ 144.1 $ 20.4 Derivatives not designated as hedging instruments Commodity contracts Current $ 3.4 $ 18.1 $ 2.8 $ 14.7 Long-term 2.7 6.3 2.5 1.6 Total derivatives not designated as hedging instruments $ 6.1 $ 24.4 $ 5.3 $ 16.3 Total current position $ 75.9 $ 43.3 $ 115.3 $ 33.6 Total long-term position 23.1 9.4 34.1 3.1 Total derivatives $ 99.0 $ 52.7 $ 149.4 $ 36.7
Pro Forma Impact of Derivatives Net in Consolidated Balance Sheet	The pro forma impact of reporting derivatives on our Consolidated Balance Sheets on a net basis is as follows: Gross Presentation Pro Forma Net Presentation March 31, 2019 Asset Liability Collateral Asset Liability Current Position Counterparties with offsetting positions or collateral $ 69.0 $ (42.0 ) $ (7.3 ) $ 43.5 $ (23.8 ) Counterparties without offsetting positions - assets 6.9 - - 6.9 - Counterparties without offsetting positions - liabilities - (1.3 ) - - (1.3 ) 75.9 (43.3 ) (7.3 ) 50.4 (25.1 ) Long Term Position Counterparties with offsetting positions or collateral 19.0 (9.1 ) - 13.5 (3.6 ) Counterparties without offsetting positions - assets 4.1 - - 4.1 - Counterparties without offsetting positions - liabilities - (0.3 ) - - (0.3 ) 23.1 (9.4 ) - 17.6 (3.9 ) Total Derivatives Counterparties with offsetting positions or collateral 88.0 (51.1 ) (7.3 ) 57.0 (27.4 ) Counterparties without offsetting positions - assets 11.0 - - 11.0 - Counterparties without offsetting positions - liabilities - (1.6 ) - - (1.6 ) $ 99.0 $ (52.7 ) $ (7.3 ) $ 68.0 $ (29.0 ) Gross Presentation Pro Forma Net Presentation December 31, 2018 Asset Liability Collateral Asset Liability Current Position Counterparties with offsetting positions or collateral $ 100.0 $ (33.6 ) $ (14.2 ) $ 70.0 $ (17.8 ) Counterparties without offsetting positions - assets 15.3 - - 15.3 - Counterparties without offsetting positions - liabilities - - - - - 115.3 (33.6 ) (14.2 ) 85.3 (17.8 ) Long Term Position Counterparties with offsetting positions or collateral 8.9 (3.1 ) - 5.9 (0.1 ) Counterparties without offsetting positions - assets 25.2 - - 25.2 - Counterparties without offsetting positions - liabilities - - - - - 34.1 (3.1 ) - 31.1 (0.1 ) Total Derivatives Counterparties with offsetting positions or collateral 108.9 (36.7 ) (14.2 ) 75.9 (17.9 ) Counterparties without offsetting positions - assets 40.5 - - 40.5 - Counterparties without offsetting positions - liabilities - - - - - $ 149.4 $ (36.7 ) $ (14.2 ) $ 116.4 $ (17.9 )
Amounts Recorded in Other Comprehensive Income (OCI) and Amounts Reclassified from OCI to Revenue	The following tables reflect amounts recorded in Other comprehensive income (“OCI”) and amounts reclassified from OCI to revenue for the periods indicated: Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Derivatives in Cash Flow Three Months Ended March 31, Hedging Relationships 2019 2018 Commodity contracts $ (38.8 ) $ 64.6 Gain (Loss) Reclassified from OCI into Income (Effective Portion) Three Months Ended March 31, Location of Gain (Loss) 2019 2018 Revenues $ 21.3 $ (26.7 )
Gain (Loss) Recognized in Income on Derivatives	The use of mark-to-market accounting for financial instruments can cause non-cash earnings volatility due to changes in the underlying commodity price indices. Location of Gain Gain (Loss) Recognized in Income on Derivatives Derivatives Not Designated Recognized in Income on Three Months Ended March 31, as Hedging Instruments Derivatives 2019 2018 Commodity contracts Revenue $ (9.5 ) $ (10.8 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Breakdown by Fair Value Hierarchy Category for Financial Instruments Included on Consolidated Balance Sheets	The following table shows a breakdown by fair value hierarchy category for (1) financial instruments measurements included on our Consolidated Balance Sheets at fair value and (2) supplemental fair value disclosures for other financial instruments: March 31, 2019 Fair Value Carrying Value Total Level 1 Level 2 Level 3 Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value: Assets from commodity derivative contracts (1) $ 97.2 $ 97.2 $ — $ 93.3 $ 3.9 Liabilities from commodity derivative contracts (1) 50.9 50.9 — 50.5 0.4 TPL contingent consideration (2) 2.4 2.4 — — 2.4 Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value: Cash and cash equivalents 111.7 111.7 — — — TRP Revolver 670.0 670.0 — 670.0 — Senior unsecured notes 6,028.5 6,268.9 — 6,268.9 — Accounts receivable securitization facility 307.6 307.6 — 307.6 — December 31, 2018 Fair Value Carrying Value Total Level 1 Level 2 Level 3 Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value: Assets from commodity derivative contracts (1) $ 144.4 $ 144.4 $ — $ 137.5 $ 6.9 Liabilities from commodity derivative contracts (1) 31.7 31.7 — 31.3 0.4 Permian Acquisition contingent consideration (3) 308.2 308.2 — — 308.2 TPL contingent consideration (2) 2.4 2.4 — — 2.4 Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value: Cash and cash equivalents 203.3 203.3 — — — TRP Revolver 700.0 700.0 — 700.0 — Senior unsecured notes 5,277.9 5,088.9 — 5,088.9 — Accounts receivable securitization facility 280.0 280.0 — 280.0 — (1) The fair value of derivative contracts in this table is presented on a different basis than the Consolidated Balance Sheets presentation as disclosed in Note 13– Derivative Instruments and Hedging Activities. The above fair values reflect the total value of each derivative contract taken as a whole, whereas the Consolidated Balance Sheets presentation is based on the individual maturity dates of estimated future settlements. As such, an individual contract could have both an asset and liability position when segregated into its current and long-term portions for Consolidated Balance Sheets classification purposes. (2) We have a contingent consideration liability for TPL’s previous acquisition of a gas gathering system and related assets, which is carried at fair value. (3) We have a contingent consideration liability related to the Permian Acquisition, which was carried at fair value as of December 31, 2018. See Note 8 – Accounts Payable and Accrued Liabilities.
Reconciliation of Changes in Fair Value of Financial Instruments Classified as Level 3	The following table summarizes the changes in fair value of our financial instruments classified as Level 3 in the fair value hierarchy: Commodity Derivative Contracts Contingent Asset/(Liability) Consideration Balance, December 31, 2018 $ 6.5 $ (310.6 ) Completion of Permian Acquisition contingent consideration earn-out period - 308.2 Unrealized gain/(loss) included in OCI (3.1 ) - Balance, March 31, 2019 $ 3.4 $ (2.4 )

Related Party Transactions - _2

Related Party Transactions - Targa (Tables)	3 Months Ended
	Mar. 31, 2019
Related Party Transactions [Abstract]
Summary of Transactions with Affiliates	The following table summarizes transactions with Targa. Management believes these transactions are executed on terms that are fair and reasonable: Three Months Ended March 31, 2019 2018 Targa billings of payroll and related costs included in operating expenses $ 54.1 $ 59.5 Targa allocation of general and administrative expense 67.8 47.3 Cash distributions to Targa based on general partner and limited partner ownership 238.5 225.7 Cash contributions from Targa related to limited partner ownership (1) — 58.8 Cash contributions from Targa to maintain its 2% general partner ownership — 1.2 __________________________________________________________________________________________________________ (1) The cash contributions from Targa related to limited partner ownership were allocated 98% to the limited partner and 2% to general partner. See Note 12 – Partnership Units and Related Matters.

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2019
Revenue From Contract With Customer [Abstract]
Summary of Estimated Minimum Revenue Expected to be Recognized in Future Related to Unsatisfied Performance Obligations	The following table includes the estimated minimum revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) at the end of the reporting period and is comprised of fixed consideration primarily attributable to contracts with minimum volume commitments and for which a guaranteed amount of revenue can be calculated . These contracts are comprised primarily of gathering and processing, fractionation, export, terminaling and storage agreements. 2019 2020 2021 and after Fixed consideration to be recognized as of March 31, 2019 $ 394.3 $ 463.0 $ 3,327.5

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2019
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Three Months Ended March 31, 2019 2018 Cash: Interest paid, net of capitalized interest (1) $ 61.2 $ 39.4 Income taxes paid, net of refunds 0.3 0.2 Non-cash investing activities: Deadstock commodity inventory transferred to property, plant and equipment $ 17.5 $ 1.7 Impact of capital expenditure accruals on property, plant and equipment (38.4 ) (22.3 ) Transfers from materials and supplies inventory to property, plant and equipment 1.1 0.4 Contribution of property, plant and equipment to investments in unconsolidated affiliates — 16.0 Change in ARO liability and property, plant and equipment 7.4 2.1 Non-cash balance sheet movements related to acquisition of related party: Intercompany payable $ — $ 1.4 Noncontrolling interest — 1.2 Lease liabilities arising from recognition of right-of-use assets: Operating lease $ 0.4 $ — Finance lease 1.5 — __________________ (1) Interest capitalized on major projects was $18.9 million and $9.6 million for the three months ended March 31, 2019 and 2018.

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2019
Segment Reporting [Abstract]
Information by Segment	Reportable segment information is shown in the following tables: Three Months Ended March 31, 2019 Gathering and Processing Logistics and Marketing Other Corporate and Eliminations Total Revenues Sales of commodities $ 247.6 $ 1,726.8 $ 2.1 $ — $ 1,976.5 Fees from midstream services 199.9 123.0 — — 322.9 447.5 1,849.8 2.1 — 2,299.4 Intersegment revenues Sales of commodities 822.8 38.4 — (861.2 ) — Fees from midstream services 1.9 5.5 — (7.4 ) — 824.7 43.9 — (868.6 ) — Revenues $ 1,272.2 $ 1,893.7 $ 2.1 $ (868.6 ) $ 2,299.4 Operating margin $ 229.0 $ 152.1 $ 2.1 $ — $ 383.2 Other financial information: Total assets (1) $ 11,713.9 $ 5,644.9 $ 87.9 $ 84.3 $ 17,531.0 Goodwill $ 46.6 $ — $ — $ — $ 46.6 Capital expenditures $ 417.8 $ 470.9 $ — $ 16.9 $ 905.6 __________________________________________________________________________________________ (1) Assets in the Corporate and Eliminations column primarily include cash, prepaids and debt issuance costs for our TRP Revolver. Three Months Ended March 31, 2018 Gathering and Processing Logistics and Marketing Other Corporate and Eliminations Total Revenues Sales of commodities $ 265.2 $ 1,926.3 $ (17.8 ) $ — $ 2,173.7 Fees from midstream services 161.3 120.6 — — 281.9 426.5 2,046.9 (17.8 ) — 2,455.6 Intersegment revenues Sales of commodities 866.5 55.7 — (922.2 ) — Fees from midstream services 1.9 6.9 — (8.8 ) — 868.4 62.6 — (931.0 ) — Revenues $ 1,294.9 $ 2,109.5 $ (17.8 ) $ (931.0 ) $ 2,455.6 Operating margin $ 220.8 $ 138.4 $ (17.8 ) $ — $ 341.4 Other financial information: Total assets (1) $ 10,908.5 $ 3,595.1 $ 103.0 $ 121.1 $ 14,727.7 Goodwill $ 256.6 $ — $ — $ — $ 256.6 Capital expenditures $ 273.2 $ 251.0 $ — $ 33.8 $ 558.0 ____________________________________________________________________________________________ (1) Assets in the Corporate and Eliminations column primarily include cash, prepaids and debt issuance costs for our TRP Revolver.
Revenues Disaggregated by Product and Service	The following table shows our consolidated revenues disaggregated by product and service for the periods presented: Three Months Ended March 31, 2019 2018 Sales of commodities: Revenue recognized from contracts with customers: Natural gas $ 411.3 $ 470.1 NGL 1,408.1 1,607.3 Condensate and crude oil 137.7 86.9 Petroleum products 7.6 48.2 1,964.7 2,212.5 Non-customer revenue: Derivative activities - Hedge 21.3 (28.0 ) Derivative activities - Non-hedge (1) (9.5 ) (10.8 ) 11.8 (38.8 ) Total sales of commodities 1,976.5 2,173.7 Fees from midstream services: Revenue recognized from contracts with customers: NGL transportation and services 36.2 41.1 Storage, terminaling and export 79.6 78.2 Gathering and processing 194.5 152.1 Other 12.6 10.5 Total fees from midstream services 322.9 281.9 Total revenues $ 2,299.4 $ 2,455.6 __________________________________________________________________________________________ (1) Represents derivative activities that are not designated as hedging instruments under ASC 815.
Reconciliation of Reportable Segment Operating Margin to Income (Loss) Before Income Taxes	The following table shows a reconciliation of reportable segment operating margin to income (loss) before income taxes for the periods presented: Three Months Ended March 31, 2019 2018 Reconciliation of reportable segment operating margin to income (loss) before income taxes: Gathering and Processing operating margin $ 229.0 $ 220.8 Logistics and Marketing operating margin 152.1 138.4 Other operating margin 2.1 (17.8 ) Depreciation and amortization expense (237.4 ) (198.1 ) General and administrative expense (77.7 ) (52.6 ) Interest income (expense), net (75.4 ) 20.2 Change in contingent considerations (9.7 ) (56.1 ) Other, net (2.0 ) 1.2 Income (loss) before income taxes $ (19.0 ) $ 56.0

Organization and Operations (De

Organization and Operations (Details) - Series A Cumulative Redeemable Perpetual Preferred Units [Member] - shares	1 Months Ended	3 Months Ended
	Oct. 31, 2015	Mar. 31, 2019	Dec. 31, 2018
Subsidiary Of Limited Liability Company Or Limited Partnership [Line Items]
Preferred units, outstanding		5,000,000	5,000,000
Preferred units dividend percentage	9.00%	9.00%

Significant Accounting Polici_3

Significant Accounting Policies (Details) - Accounting Standards Update 2016-02 [Member]	Jan. 01, 2019USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Effect on retained earnings	$ 0
Right-of-use asset, net of lease incentives and deferred rent	64,200,000
Lease incentives and deferred rent	400,000
Lease liability	$ 64,600,000

Divestitures - Additional Infor

Divestitures - Additional Information (Details) $ in Billions	Apr. 03, 2019USD ($)	Feb. 28, 2019MBbls / d
Subsequent Event [Member] | Targa Badlands LLC [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Subsidiary ownership interest sale percentage	45.00%
Cash consideration received on sale of interest on subsidiary | $	$ 1.6
Williams [Member] | Train 7 [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Fractionation-related infrastructure funded and owned percentage		100.00%
Williams [Member] | Mont Belvieu, Texas [Member] | Train 7 [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Option to purchase equity interest percentage		20.00%
Capacity of pipeline | MBbls / d		110

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Commodities	$ 176.4	$ 151.1
Materials and supplies	21.5	13.6
Total inventory	$ 197.9	$ 164.7

Property, Plant and Equipment_3

Property, Plant and Equipment and Intangible Assets - Property, Plant and Equipment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 18,182.3	$ 17,213.8
Accumulated depreciation and amortization	(4,479.2)	(4,285.5)
Property, plant and equipment, net	13,703.1	12,928.3
Intangible assets	2,736.6	2,736.6
Accumulated amortization	(796.4)	(753.4)
Intangible assets, net	$ 1,940.2	1,983.2
Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	10 years
Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	20 years
Gathering Systems [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 8,417.2	7,547.9
Gathering Systems [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	5 years
Gathering Systems [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	20 years
Processing and Fractionation Facilities [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 4,287.4	4,001
Processing and Fractionation Facilities [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	5 years
Processing and Fractionation Facilities [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	25 years
Terminaling and Storage Facilities [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 1,173	1,138.7
Terminaling and Storage Facilities [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	5 years
Terminaling and Storage Facilities [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	25 years
Transportation Assets [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 1,016.8	445.1
Transportation Assets [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	10 years
Transportation Assets [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	25 years
Other Property, Plant and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 398.6	334.3
Other Property, Plant and Equipment [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	3 years
Other Property, Plant and Equipment [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	25 years
Land [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 149.2	144.3
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	2,699.2	$ 3,602.5
Finance Lease Right-of-Use Assets [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 40.9

Property, Plant and Equipment_4

Property, Plant and Equipment and Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Property Plant And Equipment [Line Items]
Depreciation expense	$ 194.4	$ 152.4
Cumulative Impact of Adjustment [Member]
Property Plant And Equipment [Line Items]
Depreciation expense	$ 12.5

Property, Plant and Equipment_5

Property, Plant and Equipment and Intangible Assets - Intangible Assets (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Estimated amortization expense for intangible assets [Abstract]
2019	$ 171.6
2020	159.4
2021	149.5
2022	141.2
2023	$ 136
Minimum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	10 years
Maximum [Member]
Property Plant And Equipment [Line Items]
Estimated useful life	20 years

Property, Plant and Equipment_6

Property, Plant and Equipment and Intangible Assets - Schedule of Changes in Intangible Assets (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Intangible Assets, net [Roll Forward]
Balance at December 31, 2018	$ 1,983.2
Amortization	(43)
Balance at March 31, 2019	$ 1,940.2

Investments in Unconsolidated_3

Investments in Unconsolidated Affiliates - Additional Information (Details)	3 Months Ended
	Mar. 31, 2019MMcf / dJointVenturemi
Gulf Coast Fractionators LP [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	38.80%
T2 Joint Ventures [Member]
Schedule Of Equity Method Investments [Line Items]
Number of operated joint ventures acquired in Atlas mergers | JointVenture	2
T2 La Salle [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	75.00%
T2 Eagle Ford [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	50.00%
Cayenne Joint Venture [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	50.00%
Gas pipeline owns | mi	62
GCX [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	25.00%
Little Missouri [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	50.00%
Processing capacity | MMcf / d	200
Agua Blanca [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	10.00%

Investments in Unconsolidated_4

Investments in Unconsolidated Affiliates - Activity Related to Partnership's Investments in Unconsolidated Affiliates (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period		$ 490.5
Equity earnings (loss)		2.8	$ 1.5
Cash Distributions		(4.8)
Contributions		117.4
Balance at end of period		605.9
Gulf Coast Fractionators LP [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period		40.3
Equity earnings (loss)		4.3
Cash Distributions		(2.2)
Contributions		0
Balance at end of period		42.4
T2 La Salle [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period	[1]	49.3
Equity earnings (loss)	[1]	(1.5)
Cash Distributions	[1]	0
Contributions	[1]	0
Balance at end of period	[1]	47.8
T2 Eagle Ford [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period	[1]	99
Equity earnings (loss)	[1]	(2.4)
Cash Distributions	[1]	0
Contributions	[1]	0
Balance at end of period	[1]	96.6
Cayenne Joint Venture [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period		16.6
Equity earnings (loss)		1.9
Cash Distributions		(2.6)
Contributions		0
Balance at end of period		15.9
GCX [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period	[2]	211.6
Equity earnings (loss)	[2]	0.6
Cash Distributions	[2]	0
Contributions	[2]	110.4
Balance at end of period	[2]	322.6
Little Missouri [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period		67.3
Equity earnings (loss)		0
Cash Distributions		0
Contributions		7
Balance at end of period		74.3
Agua Blanca [Member]
Schedule Of Equity Method Investments [Line Items]
Balance at beginning of period		6.4
Equity earnings (loss)		(0.1)
Cash Distributions		0
Contributions		0
Balance at end of period		$ 6.3
[1]	As of March 31, 2019, $24.3 million of unamortized excess fair value over the T2 LaSalle and T2 Eagle Ford capital accounts remained. These basis differences, which are attributable to the underlying depreciable tangible gathering assets, are being amortized on a straight-line basis as components of equity earnings over the estimated 20-year useful lives of the underlying assets.
[2]	Our 25% interest in GCX is owned by Targa GCX Pipeline LLC (“GCX DevCo JV”), of which we own a 20% interest. GCX DevCo JV is accounted for on a consolidated basis in our consolidated financial statements.

Investments in Unconsolidated_5

Investments in Unconsolidated Affiliates - Activity Related to Partnership's Investments in Unconsolidated Affiliates (Parenthetical) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
GCX DevCo JV [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	20.00%
GCX DevCo JV [Member] | GCX [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership interest	25.00%
T2 LaSalle and T2 Eagle Ford [Member]
Schedule Of Equity Method Investments [Line Items]
Unamortized excess fair value	$ 24.3
Preliminary estimated useful lives of the underlying assets	20 years

Accounts Payable and Accrued _3

Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Components of accounts payable and accrued liabilities [Abstract]
Commodities	$ 779.3	$ 721.9
Other goods and services	379.4	474.5
Interest	91	79.4
Income and other taxes	40.4	45.4
Other	11.4	7.5
Accounts payable and accrued liabilities	1,619.4	1,636.9
Permian Acquisition [Member]
Components of accounts payable and accrued liabilities [Abstract]
Permian Acquisition contingent consideration	$ 317.9	$ 308.2

Accounts Payable and Accrued _4

Accounts Payable and Accrued Liabilities - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Payables And Accruals [Line Items]
Outstanding checks	$ 28,900,000		$ 52,200,000
Change in contingent considerations	9,700,000	$ 56,100,000
Permian Acquisition [Member]
Payables And Accruals [Line Items]
Fair value of first potential earn-out payment	0
Change in contingent considerations	$ 9,700,000	$ 56,000,000

Debt Obligations (Details)

Debt Obligations (Details) - USD ($) $ in Millions		Mar. 31, 2019	Dec. 31, 2018
Current:
Accounts receivable securitization facility, due December 2019	[1]	$ 307.6	$ 280
Current debt		307.6	1,029.4
Debt issuance costs, net of amortization			(1.5)
Finance lease liabilities		10.5
Current debt obligations		318.1	1,027.9
Long-term [Abstract]
Long-term debt		6,683.5	5,197.4
Long-term debt including unamortized premium (discount)		6,698.5	5,228.5
Debt issuance costs, net of amortization		(42.7)	(31.1)
Finance lease liabilities		27.7
Total debt obligations		7,001.6	6,225.3
Irrevocable standby letters of credit outstanding	[2]	69.8	79.5
Senior Unsecured Notes [Member] | Senior Unsecured 4 1/8% Notes due November 2019 [Member]
Current:
Long-term debt, current			749.4
Senior Unsecured Notes [Member] | Senior Unsecured 5 1/4% Notes due May 2023 [Member]
Long-term [Abstract]
Long-term debt		559.6	559.6
Senior Unsecured Notes [Member] | Senior Unsecured 4 1/4% Notes due November 2023 [Member]
Long-term [Abstract]
Long-term debt		583.9	583.9
Senior Unsecured Notes [Member] | Senior Unsecured 6 3/4% Notes due March 2024 [Member]
Long-term [Abstract]
Long-term debt		580.1	580.1
Senior Unsecured Notes [Member] | Senior Unsecured 5 1/8% Notes due February 2025 [Member]
Long-term [Abstract]
Long-term debt		500	500
Senior Unsecured Notes [Member] | Senior Unsecured 5⅞% Notes due April 2026 [Member]
Long-term [Abstract]
Long-term debt		1,000	1,000
Senior Unsecured Notes [Member] | Senior Unsecured 5 3/8% Notes due February 2027 [Member]
Long-term [Abstract]
Long-term debt		500	500
Senior Unsecured Notes [Member] | Senior Unsecured 6 1/2% Notes due July 2027 [Member]
Long-term [Abstract]
Long-term debt		750
Senior Unsecured Notes [Member] | Senior Unsecured 5% Notes due January 2028 [Member]
Long-term [Abstract]
Long-term debt		750	750
Senior Unsecured Notes [Member] | Senior Unsecured 6 7/8% Notes due January 2029 [Member]
Long-term [Abstract]
Long-term debt		750
Senior Unsecured Notes [Member] | Targa Pipeline Partners LP [Member] | Senior Unsecured 4 3/4% Notes due November 2021 [Member]
Long-term [Abstract]
Long-term debt	[3]	6.5	6.5
Senior Unsecured Notes [Member] | Targa Pipeline Partners LP [Member] | Senior Unsecured 5 7/8% Notes due August 2023 [Member]
Long-term [Abstract]
Long-term debt	[3]	48.1	48.1
Unamortized premium		0.3	0.3
Revolving Credit Facility [Member] | Senior Secured Revolving Credit Facility, Variable Rate, due June 2023 [Member]
Long-term [Abstract]
Long-term debt	[2]	$ 670	$ 700
[1]	As of March 31, 2019, we had $337.6 million of qualifying receivables under our $400.0 million accounts receivable securitization facility, resulting in availability of $30.0 million.
[2]	As of March 31, 2019, availability under our $2.2 billion senior secured revolving credit facility (“TRP Revolver”) was $1,460.2 million.
[3]	“TPL” refers to Targa Pipeline Partners LP

Debt Obligations (Parenthetical

Debt Obligations (Parenthetical) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018	Jan. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Proceeds from borrowings under accounts receivable securitization facility		$ 378	$ 0
Accounts receivable securitization facility	[1]	$ 307.6			$ 280
Revolving Credit Facility [Member] | Senior Secured Revolving Credit Facility, Variable Rate, due June 2023 [Member]
Debt Instrument [Line Items]
Maturity date	[2]	Jun. 30, 2023
Maximum borrowing capacity		$ 2,200
Remaining borrowing capacity		1,460.2
Accounts Receivable Securitization Facility [Member]
Debt Instrument [Line Items]
Proceeds from borrowings under accounts receivable securitization facility		337.6
Accounts receivable securitization facility		400
Availability amount under accounts receivable securitization		$ 30
Accounts Receivable Securitization Facility [Member] | Accounts Receivable Securitization Facility Due December 2019 [Member]
Debt Instrument [Line Items]
Maturity date	[1]	Dec. 31, 2019
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Interest rate on fixed rate debt				4.125%
Senior Unsecured Notes [Member] | Senior Unsecured 4 1/8% Notes due November 2019 [Member]
Debt Instrument [Line Items]
Maturity date		Nov. 30, 2019
Interest rate on fixed rate debt		4.125%		4.125%
Senior Unsecured Notes [Member] | Senior Unsecured 5 1/4% Notes due May 2023 [Member]
Debt Instrument [Line Items]
Maturity date		May 31, 2023
Interest rate on fixed rate debt		5.25%
Senior Unsecured Notes [Member] | Senior Unsecured 4 1/4% Notes due November 2023 [Member]
Debt Instrument [Line Items]
Maturity date		Nov. 30, 2023
Interest rate on fixed rate debt		4.25%
Senior Unsecured Notes [Member] | Senior Unsecured 6 3/4% Notes due March 2024 [Member]
Debt Instrument [Line Items]
Maturity date		Mar. 31, 2024
Interest rate on fixed rate debt		6.75%
Senior Unsecured Notes [Member] | Senior Unsecured 5 1/8% Notes due February 2025 [Member]
Debt Instrument [Line Items]
Maturity date		Feb. 28, 2025
Interest rate on fixed rate debt		5.125%
Senior Unsecured Notes [Member] | Senior Unsecured 6 1/2% Notes due July 2027 [Member]
Debt Instrument [Line Items]
Maturity date		Jul. 31, 2027
Interest rate on fixed rate debt		6.50%
Senior Unsecured Notes [Member] | Senior Unsecured 5⅞% Notes due April 2026 [Member]
Debt Instrument [Line Items]
Maturity date		Apr. 30, 2026
Interest rate on fixed rate debt		5.875%
Senior Unsecured Notes [Member] | Senior Unsecured 5 3/8% Notes due February 2027 [Member]
Debt Instrument [Line Items]
Maturity date		Feb. 28, 2027
Interest rate on fixed rate debt		5.375%
Senior Unsecured Notes [Member] | Senior Unsecured 5% Notes due January 2028 [Member]
Debt Instrument [Line Items]
Maturity date		Jan. 31, 2028
Interest rate on fixed rate debt		5.00%
Senior Unsecured Notes [Member] | Senior Unsecured 6 7/8% Notes due January 2029 [Member]
Debt Instrument [Line Items]
Maturity date		Jan. 31, 2029
Interest rate on fixed rate debt		6.875%
Senior Unsecured Notes [Member] | Targa Pipeline Partners LP [Member] | Senior Unsecured 4 3/4% Notes due November 2021 [Member]
Debt Instrument [Line Items]
Maturity date	[3]	Nov. 30, 2021
Interest rate on fixed rate debt	[3]	4.75%
Senior Unsecured Notes [Member] | Targa Pipeline Partners LP [Member] | Senior Unsecured 5 7/8% Notes due August 2023 [Member]
Debt Instrument [Line Items]
Maturity date	[3]	Aug. 31, 2023
Interest rate on fixed rate debt	[3]	5.875%
[1]	As of March 31, 2019, we had $337.6 million of qualifying receivables under our $400.0 million accounts receivable securitization facility, resulting in availability of $30.0 million.
[2]	As of March 31, 2019, availability under our $2.2 billion senior secured revolving credit facility (“TRP Revolver”) was $1,460.2 million.
[3]	“TPL” refers to Targa Pipeline Partners LP

Debt Obligations - Interest Rat

Debt Obligations - Interest Rates on Variable-Rate Debt Obligations (Details)	Mar. 31, 2019
Accounts Receivable Securitization Facility [Member]
Range of interest rates and weighted average interest rate [Abstract]
Range of interest rates incurred	3.40%
Weighted average interest rate incurred	3.40%
TRP Revolver [Member]
Range of interest rates and weighted average interest rate [Abstract]
Weighted average interest rate incurred	4.10%
TRP Revolver [Member] | Minimum [Member]
Range of interest rates and weighted average interest rate [Abstract]
Range of interest rates incurred	3.80%
TRP Revolver [Member] | Maximum [Member]
Range of interest rates and weighted average interest rate [Abstract]
Range of interest rates incurred	4.30%

Debt Obligations - Senior Unsec

Debt Obligations - Senior Unsecured Notes Issuances (Details) - Senior Unsecured Notes [Member] $ in Millions	1 Months Ended
	Jan. 31, 2019USD ($)
Debt Instrument [Line Items]
Interest rate on fixed rate debt	4.125%
6 1/2% Senior Notes due July 2027 [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 750
Interest rate on fixed rate debt	6.50%
Maturity date	Jul. 31, 2027
6 7/8% Senior Notes due January 2029 [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 750
Interest rate on fixed rate debt	6.875%
Maturity date	Jan. 31, 2029
6 1/2% Senior Notes due July 2027 and 6 7/8% Senior Notes due January 2029 [Member]
Debt Instrument [Line Items]
Net proceeds from senior notes	$ 1,487.3

Debt Obligations - Debt Extingu

Debt Obligations - Debt Extinguishment (Details) - Senior Unsecured Notes [Member] - USD ($) $ in Millions	1 Months Ended
	Jan. 31, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Interest rate on fixed rate debt	4.125%
4 1/8% Senior Notes due November 2019 [Member]
Debt Instrument [Line Items]
Interest rate on fixed rate debt	4.125%	4.125%
Write off debt issuance cost	$ 1.4

Other Long-term Liabilities - S

Other Long-term Liabilities - Schedule of Other Long-term Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Other Liabilities Noncurrent [Abstract]
Asset retirement obligations	$ 63.4	$ 55
Deferred revenue	174.6	175.5
Operating lease liabilities	17.3
Other liabilities	3	3.3
Total long-term liabilities	$ 258.3	$ 233.8

Other Long-term Liabilities - A

Other Long-term Liabilities - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred Revenue [Abstract]
Deferred revenue	$ 174.6	$ 175.5
Channelview Splitter [Member] | Noble Americas Corp [Member]
Deferred Revenue [Abstract]
Deferred revenue		$ 129	$ 129	$ 129

Other Long-term Liabilities - C

Other Long-term Liabilities - Changes In Deferred Revenue (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Other Liabilities Noncurrent [Abstract]
Balance at December 31, 2018	$ 175.5
Revenue recognized	(0.9)
Balance at March 31, 2019	$ 174.6

Leases - Additional Information

Leases - Additional Information (Details)	Mar. 31, 2019
Lessee Lease Description [Line Items]
Weighted average remaining lease term for operating lease	4 years
Weighted average remaining lease term for finance lease	3 years
Weighted average discount rate for operating leases	3.90%
Weighted average discount rate for finance leases	3.90%
Minimum [Member]
Lessee Lease Description [Line Items]
Leases, remaining lease term	1 year
Maximum [Member]
Lessee Lease Description [Line Items]
Leases, remaining lease term	6 years
Options to extend lease term	10 years

Leases - Summary of Balances of

Leases - Summary of Balances of Right-of-Use Assets and Liabilities of Finance and Operating Leases (Details) $ in Millions	Mar. 31, 2019USD ($)
Right-of-use assets
Operating leases, gross	$ 25.2
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsNoncurrent
Finance leases, gross	$ 40.9
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentGross
Current:
Operating leases	$ 6.6
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Finance leases	$ 10.5
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:LiabilitiesCurrent
Non-current:
Operating leases	$ 17.3
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent
Finance leases	$ 27.7
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:LiabilitiesNoncurrent

Leases - Components of Lease Ex

Leases - Components of Lease Expense (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Lease cost
Operating lease cost	$ 1.9
Short-term lease cost	7.6
Variable lease cost	1.3
Finance lease cost
Amortization of right-of-use assets	3.1
Interest expense	0.4
Total lease cost	$ 14.3

Leases - Summary of Other Suppl

Leases - Summary of Other Supplemental Information Related to Leases (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows for operating leases	$ 1.9
Operating cash flows for finance leases	0.4
Financing cash flows for finance leases	$ 2.7	$ 0

Leases - Summary of Maturities

Leases - Summary of Maturities of Lease Liabilities under Non-cancellable Leases (Details) $ in Millions	Mar. 31, 2019USD ($)
Future Minimum Lease Payments - Operating Leases
2019	$ 7.4
2020	5.6
2021	5.3
2022	4.2
2023	2.4
Thereafter	1
Total undiscounted cash flows	25.9
Less imputed interest	(2)
Total lease liabilities	23.9
Future Minimum Lease Payments - Finance Leases
2019	11.8
2020	11
2021	9.2
2022	8.2
2023	1
Total undiscounted cash flows	41.2
Less imputed interest	(3)
Total lease liabilities	$ 38.2

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Payments under Non-cancellable Leases (Details) $ in Millions	Dec. 31, 2018USD ($)
Future non-cancelable commitments for each of the next five fiscal years and in Aggregate Thereafter [Abstract]
2019	$ 20.5
2020	17.7
2021	14.9
2022	12.6
2023	6
Thereafter	1.7
Total payments	$ 73.4

Partnership Units and Related_3

Partnership Units and Related Matters - Distributions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Distributions declared and/or paid by the Partnership [Abstract]
Date Paid	Apr. 5, 2019	Feb. 13, 2019
Total Distributions	$ 241.3		$ 228.5
Distributions Paid [Member]
Distributions declared and/or paid by the Partnership [Abstract]
Total Distributions	437.8	$ 241.3
Distributions to Targa Resources Corp.	$ 435	$ 238.5

Partnership Units and Related_4

Partnership Units and Related Matters (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended
	Apr. 30, 2019	Oct. 31, 2015	Mar. 31, 2019	Dec. 31, 2018
Distributions declared and/or paid by the Partnership [Abstract]
Distributions payable date			Apr. 5, 2019	Feb. 13, 2019
Subsequent Event [Member]
Distributions declared and/or paid by the Partnership [Abstract]
Date of declaration for cash distribution	2019-04
Cash distribution declared per unit (in dollars per share)	$ 0.1875
Distributions to Targa Resources Corp.	$ 0.9
Distributions payable date	May 15, 2019
Series A Preferred Limited Partner Units [Member]
Limited Partners Capital Account [Line Items]
Series A preferred limited partners units issued (in units)			5,000,000	5,000,000
Preferred units dividend percentage		9.00%	9.00%
Distribution to holders of preferred units			$ 2.8
Series A Preferred Limited Partner Units [Member] | London Interbank Offered Rate (LIBOR)
Limited Partners Capital Account [Line Items]
Percentage of variable interest rate for distribution on preferred units upon maturity		7.71%
TRC/TRP Merger | Limited Partners [Member]
Limited Partners Capital Account [Line Items]
Percentage of capital contribution towards partner's interest maintained			98.00%
TRC/TRP Merger | Targa Resources GP LLC [Member]
Limited Partners Capital Account [Line Items]
Percentage of general partner's interest maintained			2.00%
Contributions from Targa Resources Corp. (in units)			0

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities - Notional Volumes Of The Partnership's Commodity Derivative Contracts (Details)	3 Months Ended
	Mar. 31, 2019MMBTUbbl
Year 2019 [Member] | Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	175,364
Year 2019 [Member] | Swaps [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	17,903
Year 2019 [Member] | Swaps [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	4,266
Year 2019 [Member] | Basis Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	111,100
Year 2019 [Member] | Future | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	9,735
Year 2019 [Member] | Options [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	410
Year 2019 [Member] | Options [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	590
Year 2020 [Member] | Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	79,930
Year 2020 [Member] | Swaps [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	13,267
Year 2020 [Member] | Swaps [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	2,390
Year 2020 [Member] | Basis Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	189,119
Year 2020 [Member] | Future | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	4,645
Year 2020 [Member] | Options [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2020 [Member] | Options [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2021 [Member] | Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	52,055
Year 2021 [Member] | Swaps [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	3,676
Year 2021 [Member] | Swaps [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	1,404
Year 2021 [Member] | Basis Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	166,658
Year 2021 [Member] | Future | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2021 [Member] | Options [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2021 [Member] | Options [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2022 [Member] | Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	0
Year 2022 [Member] | Swaps [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2022 [Member] | Swaps [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2022 [Member] | Basis Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	150,000
Year 2022 [Member] | Future | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2022 [Member] | Options [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2022 [Member] | Options [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2023 [Member] | Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	0
Year 2023 [Member] | Swaps [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2023 [Member] | Swaps [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2023 [Member] | Basis Swaps [Member] | Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) | MMBTU	95,000
Year 2023 [Member] | Future | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2023 [Member] | Options [Member] | NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0
Year 2023 [Member] | Options [Member] | Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	0

Derivative Instruments and He_4

Derivative Instruments and Hedging Activities - Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative assets	$ 99	$ 149.4
Derivative assets	75.9	115.3
Derivative assets	23.1	34.1
Derivative liabilities	52.7	36.7
Derivative liabilities	43.3	33.6
Derivative liabilities	9.4	3.1
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	92.9	144.1
Derivative liabilities	28.3	20.4
Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Current Assets from Risk Management Activities [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	72.5	112.5
Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Long-term Assets from Risk Management Activities [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	20.4	31.6
Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Current Liabilities from Risk Management Activities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	25.2	18.9
Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Long-term Position [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	3.1	1.5
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	6.1	5.3
Derivative liabilities	24.4	16.3
Not Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Current Assets from Risk Management Activities [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	3.4	2.8
Not Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Long-term Assets from Risk Management Activities [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	2.7	2.5
Not Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Current Liabilities from Risk Management Activities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	18.1	14.7
Not Designated as Hedging Instrument [Member] | Commodity Contracts [Member] | Long-term Position [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 6.3	$ 1.6

Derivative Instruments and He_5

Derivative Instruments and Hedging Activities - Pro Forma Impact - Offsetting Assets (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative Asset [Abstract]
Gross asset	$ 99	$ 149.4
Pro forma net presentation, asset, total	68	116.4
Counterparties with Offsetting Position or Collateral [Member]
Derivative Asset [Abstract]
Gross asset	88	108.9
Pro forma net presentation, asset	57	75.9
Counterparties without Offsetting Position [Member]
Derivative Asset [Abstract]
Gross asset	11	40.5
Pro forma net presentation, asset	11	40.5
Current Position [Member]
Derivative Asset [Abstract]
Gross asset	75.9	115.3
Pro forma net presentation, asset, current	50.4	85.3
Current Position [Member] | Counterparties with Offsetting Position or Collateral [Member]
Derivative Asset [Abstract]
Gross asset	69	100
Pro forma net presentation, asset	43.5	70
Current Position [Member] | Counterparties without Offsetting Position [Member]
Derivative Asset [Abstract]
Gross asset	6.9	15.3
Pro forma net presentation, asset	6.9	15.3
Long-term Position [Member]
Derivative Asset [Abstract]
Gross asset	23.1	34.1
Pro forma net presentation, asset, noncurrent	17.6	31.1
Long-term Position [Member] | Counterparties with Offsetting Position or Collateral [Member]
Derivative Asset [Abstract]
Gross asset	19	8.9
Pro forma net presentation, asset	13.5	5.9
Long-term Position [Member] | Counterparties without Offsetting Position [Member]
Derivative Asset [Abstract]
Gross asset	4.1	25.2
Pro forma net presentation, asset	$ 4.1	$ 25.2

Derivative Instruments and He_6

Derivative Instruments and Hedging Activities - Pro Forma Impact - Offsetting Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative Liability [Abstract]
Gross liability	$ (52.7)	$ (36.7)
Pro forma net presentation, liability, total	(29)	(17.9)
Counterparties with Offsetting Position or Collateral [Member]
Derivative Liability [Abstract]
Gross liability	(51.1)	(36.7)
Pro forma net presentation, liability, total	(27.4)	(17.9)
Counterparties without Offsetting Position [Member]
Derivative Liability [Abstract]
Gross liability	(1.6)
Pro forma net presentation, liability, total	(1.6)
Current Position [Member]
Derivative Liability [Abstract]
Gross liability	(43.3)	(33.6)
Pro forma net presentation, liability, current	(25.1)	(17.8)
Current Position [Member] | Counterparties with Offsetting Position or Collateral [Member]
Derivative Liability [Abstract]
Gross liability	(42)	(33.6)
Pro forma net presentation, liability, current	(23.8)	(17.8)
Current Position [Member] | Counterparties without Offsetting Position [Member]
Derivative Liability [Abstract]
Gross liability	(1.3)
Pro forma net presentation, liability, current	(1.3)
Long-term Position [Member]
Derivative Liability [Abstract]
Gross liability	(9.4)	(3.1)
Pro forma net presentation, liability, noncurrent	(3.9)	(0.1)
Long-term Position [Member] | Counterparties with Offsetting Position or Collateral [Member]
Derivative Liability [Abstract]
Gross liability	(9.1)	(3.1)
Pro forma net presentation, liability, noncurrent	(3.6)	$ (0.1)
Long-term Position [Member] | Counterparties without Offsetting Position [Member]
Derivative Liability [Abstract]
Gross liability	(0.3)
Pro forma net presentation, liability, noncurrent	$ (0.3)

Derivative Instruments and He_7

Derivative Instruments and Hedging Activities - Pro Forma Impact - Offsetting Collateral (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative Asset [Abstract]
Gross collateral	$ (7.3)	$ (14.2)
Counterparties with Offsetting Position or Collateral [Member]
Derivative Asset [Abstract]
Gross collateral	(7.3)	(14.2)
Current Position [Member]
Derivative Asset [Abstract]
Gross collateral	(7.3)	(14.2)
Current Position [Member] | Counterparties with Offsetting Position or Collateral [Member]
Derivative Asset [Abstract]
Gross collateral	$ (7.3)	$ (14.2)

Derivative Instruments and He_8

Derivative Instruments and Hedging Activities - Additional Information (Details) $ in Millions	Mar. 31, 2019USD ($)
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Estimated fair value of derivative instruments, net asset	$ 46.3
Amount expected to reclassify commodity hedge related deferred gains to earnings before income taxes	64.6
Amount of deferred gains to be reclassified into earnings before income taxes over next twelve months	$ 47.3

Derivative Instruments and He_9

Derivative Instruments and Hedging Activities - Amounts Included in OCI, Income and AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from OCI into Income (Effective Portion)	$ 21.3	$ (26.7)
Commodity Contracts [Member] | Revenues [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(9.5)	(10.8)
Cash Flow Hedging [Member] | Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ (38.8)	$ 64.6

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) $ in Millions	Mar. 31, 2019USD ($)Swap
Fair Value Disclosures [Abstract]
Derivatives financial instruments, fair value, net	$ 46.3
Derivative fair value of net liability if commodity price increases by 10 percent	40.1
Derivative fair value of net asset if commodity price decreases by 10 percent	$ 129.2
Number of natural gas basis swaps categorized as Level 3 | Swap	13

Fair Value Measurements - Break

Fair Value Measurements - Breakdown by Fair Value Hierarchy Category for Financial Instruments (Details) - USD ($) $ in Millions		Mar. 31, 2019	Dec. 31, 2018
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Assets from commodity derivative contracts		$ 68	$ 116.4
Liabilities from commodity derivative contracts		29	17.9
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Accounts receivable securitization facility	[1]	307.6	280
Carrying Value [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Assets from commodity derivative contracts	[2]	97.2	144.4
Liabilities from commodity derivative contracts	[2]	50.9	31.7
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Cash and cash equivalents		111.7	203.3
Accounts receivable securitization facility		307.6	280
Carrying Value [Member] | Permian Acquisition [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Contingent consideration	[3]		308.2
Carrying Value [Member] | TRP Revolver [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Long-term debt		670	700
Carrying Value [Member] | Targa Pipeline Partners LP [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Contingent consideration	[4]	2.4	2.4
Carrying Value [Member] | Senior Unsecured Notes [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Long-term debt		6,028.5	5,277.9
Fair Value [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Assets from commodity derivative contracts	[2]	97.2	144.4
Liabilities from commodity derivative contracts	[2]	50.9	31.7
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Cash and cash equivalents		111.7	203.3
Accounts receivable securitization facility		307.6	280
Fair Value [Member] | Permian Acquisition [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Contingent consideration	[3]		308.2
Fair Value [Member] | TRP Revolver [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Long-term debt		670	700
Fair Value [Member] | Targa Pipeline Partners LP [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Contingent consideration	[4]	2.4	2.4
Fair Value [Member] | Senior Unsecured Notes [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Long-term debt		6,268.9	5,088.9
Fair Value [Member] | Level 2 [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Assets from commodity derivative contracts	[2]	93.3	137.5
Liabilities from commodity derivative contracts	[2]	50.5	31.3
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Accounts receivable securitization facility		307.6	280
Fair Value [Member] | Level 2 [Member] | TRP Revolver [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Long-term debt		670	700
Fair Value [Member] | Level 2 [Member] | Senior Unsecured Notes [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value [Abstract]
Long-term debt		6,268.9	5,088.9
Fair Value [Member] | Level 3 [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Assets from commodity derivative contracts	[2]	3.9	6.9
Liabilities from commodity derivative contracts	[2]	0.4	0.4
Fair Value [Member] | Level 3 [Member] | Permian Acquisition [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Contingent consideration	[3]		308.2
Fair Value [Member] | Level 3 [Member] | Targa Pipeline Partners LP [Member]
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value [Abstract]
Contingent consideration	[4]	$ 2.4	$ 2.4
[1]	As of March 31, 2019, we had $337.6 million of qualifying receivables under our $400.0 million accounts receivable securitization facility, resulting in availability of $30.0 million.
[2]	The fair value of derivative contracts in this table is presented on a different basis than the Consolidated Balance Sheets presentation as disclosed in Note 13– Derivative Instruments and Hedging Activities. The above fair values reflect the total value of each derivative contract taken as a whole, whereas the Consolidated Balance Sheets presentation is based on the individual maturity dates of estimated future settlements. As such, an individual contract could have both an asset and liability position when segregated into its current and long-term portions for Consolidated Balance Sheets classification purposes.
[3]	We have a contingent consideration liability related to the Permian Acquisition, which was carried at fair value as of December 31, 2018. See Note 8 – Accounts Payable and Accrued Liabilities.
[4]	We have a contingent consideration liability for TPL’s previous acquisition of a gas gathering system and related assets, which is carried at fair value.

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Fair Value of Financial Instruments Classified as Level 3 (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Contingent Consideration [Member]
Changes in fair value of financial instruments classified as Level 3 in fair value hierarchy [Roll Forward]
Balance, beginning of period	$ (310.6)
Balance, end of period	(2.4)
Permian Acquisition [Member] | Contingent Consideration [Member]
Changes in fair value of financial instruments classified as Level 3 in fair value hierarchy [Roll Forward]
Completion of contingent consideration earn-out period	308.2
Commodity Derivative Contracts Asset/(Liability) [Member]
Changes in fair value of financial instruments classified as Level 3 in fair value hierarchy [Roll Forward]
Balance, beginning of period	6.5
Unrealized gain/(loss) included in OCI	(3.1)
Balance, end of period	$ 3.4

Related Party Transactions - _3

Related Party Transactions - Targa - Summary of Transactions with Affiliates (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Summary of transactions with Targa [Abstract]
Cash distributions to Targa based on general partner and limited partner ownership		$ 241.3	$ 228.5
Cash contributions from Targa related to limited partner ownership		0	58.8
Targa Resources Corp. [Member]
Summary of transactions with Targa [Abstract]
Targa billings of payroll and related costs included in operating expenses		54.1	59.5
Targa allocation of general and administrative expense		67.8	47.3
Cash distributions to Targa based on general partner and limited partner ownership		$ 238.5	225.7
Cash contributions from Targa related to limited partner ownership	[1]		58.8
Contributions from Targa Resources Corp			$ 1.2
Percentage of general partner's interest maintained		2.00%
[1]	The cash contributions from Targa related to limited partner ownership were allocated 98% to the limited partner and 2% to general partner. See Note 12 – Partnership Units and Related Matters.

Related Party Transactions - _4

Related Party Transactions - Targa - Summary of Transactions with Affiliates (Parenthetical) (Details) - Targa Resources Corp. [Member]	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction [Line Items]
Percentage of general partner's interest maintained	2.00%
Limited Partners [Member]
Related Party Transaction [Line Items]
Percentage of capital contribution towards partner's interest maintained	98.00%	98.00%
Targa Resources GP LLC [Member]
Related Party Transaction [Line Items]
Percentage of general partner's interest maintained	2.00%	2.00%

Contingencies - Additional Info

Contingencies - Additional Information (Details)	Feb. 26, 2019USD ($)
Environment Proceeding [Member] | Compliance Improvements [Member]
Loss Contingencies [Line Items]
Contingencies penalty amount	$ 220,000

Revenue - Estimated Minimum Rev

Revenue - Estimated Minimum Revenue Expected to be Recognized in Future Related to Unsatisfied Performance Obligations (Details) - Fixed Price Contract [Member] $ in Millions	Mar. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-04-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Fixed consideration to be recognized	$ 394.3
Estimated remaining duration of contracts	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Fixed consideration to be recognized	$ 463
Estimated remaining duration of contracts	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-01-01
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Fixed consideration to be recognized	$ 3,327.5
Estimated remaining duration of contracts

Revenue - Additional Informatio

Revenue - Additional Information (Details) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-04-01	Mar. 31, 2019
Minimum [Member]
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Estimated remaining duration of contracts	1 year
Maximum [Member]
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Estimated remaining duration of contracts	20 years

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Cash [Abstract]
Interest paid, net of capitalized interest	[1]	$ 61.2	$ 39.4
Income taxes paid, net of refunds		0.3	0.2
Non-cash investing activities [Abstract]
Deadstock commodity inventory transferred to property, plant and equipment		17.5	1.7
Impact of capital expenditure accruals on property, plant and equipment		(38.4)	(22.3)
Transfers from materials and supplies inventory to property, plant and equipment		1.1	0.4
Contribution of property, plant and equipment to investments in unconsolidated affiliates			16
Change in ARO liability and property, plant and equipment		7.4	2.1
Non-cash balance sheet movements related to acquisition of related party:
Intercompany payable			1.4
Noncontrolling interest			$ 1.2
Lease liabilities arising from recognition of right-of-use assets:
Operating lease		0.4
Finance lease		$ 1.5
[1]	Interest capitalized on major projects was $18.9 million and $9.6 million for the three months ended March 31, 2019 and 2018.

Supplemental Cash Flow Inform_4

Supplemental Cash Flow Information (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Supplemental Cash Flow Information [Abstract]
Interest capitalized on major projects	$ 18.9	$ 9.6

Segment Information - Additiona

Segment Information - Additional Information (Details)	3 Months Ended
	Mar. 31, 2019Segment
Segment Reporting [Abstract]
Number of reportable segments	2

Segment Information, Revenues a

Segment Information, Revenues and Operating Margin (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues [Abstract]
Revenues	$ 2,299.4	$ 2,455.6
Operating margin	383.2	341.4
Sales of Commodities [Member]
Revenues [Abstract]
Revenues	1,976.5	2,173.7
Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	322.9	281.9
Gathering and Processing [Member]
Revenues [Abstract]
Revenues	1,272.2	1,294.9
Operating margin	229	220.8
Logistics and Marketing [Member]
Revenues [Abstract]
Revenues	1,893.7	2,109.5
Operating margin	152.1	138.4
Other [Member]
Revenues [Abstract]
Revenues	2.1	(17.8)
Operating margin	2.1	(17.8)
Corporate and Elimination [Member]
Revenues [Abstract]
Revenues	(868.6)	(931)
Operating Segments [Member]
Revenues [Abstract]
Revenues	2,299.4	2,455.6
Operating Segments [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	1,976.5	2,173.7
Operating Segments [Member] | Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	322.9	281.9
Operating Segments [Member] | Gathering and Processing [Member]
Revenues [Abstract]
Revenues	447.5	426.5
Operating Segments [Member] | Gathering and Processing [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	247.6	265.2
Operating Segments [Member] | Gathering and Processing [Member] | Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	199.9	161.3
Operating Segments [Member] | Logistics and Marketing [Member]
Revenues [Abstract]
Revenues	1,849.8	2,046.9
Operating Segments [Member] | Logistics and Marketing [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	1,726.8	1,926.3
Operating Segments [Member] | Logistics and Marketing [Member] | Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	123	120.6
Operating Segments [Member] | Other [Member]
Revenues [Abstract]
Revenues	2.1	(17.8)
Operating Segments [Member] | Other [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	2.1	(17.8)
Intersegment Eliminations [Member] | Gathering and Processing [Member]
Revenues [Abstract]
Revenues	824.7	868.4
Intersegment Eliminations [Member] | Gathering and Processing [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	822.8	866.5
Intersegment Eliminations [Member] | Gathering and Processing [Member] | Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	1.9	1.9
Intersegment Eliminations [Member] | Logistics and Marketing [Member]
Revenues [Abstract]
Revenues	43.9	62.6
Intersegment Eliminations [Member] | Logistics and Marketing [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	38.4	55.7
Intersegment Eliminations [Member] | Logistics and Marketing [Member] | Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	5.5	6.9
Intersegment Eliminations [Member] | Corporate and Elimination [Member]
Revenues [Abstract]
Revenues	(868.6)	(931)
Intersegment Eliminations [Member] | Corporate and Elimination [Member] | Sales of Commodities [Member]
Revenues [Abstract]
Revenues	(861.2)	(922.2)
Intersegment Eliminations [Member] | Corporate and Elimination [Member] | Fees from Midstream Services [Member]
Revenues [Abstract]
Revenues	$ (7.4)	$ (8.8)

Segment Information, Other Fina

Segment Information, Other Financial Information (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Other financial information [Abstract]
Total assets		$ 17,531		$ 16,890.1
Goodwill		46.6		$ 46.6
Operating Segments [Member]
Other financial information [Abstract]
Total assets	[1]	17,531	$ 14,727.7
Goodwill		46.6	256.6
Capital expenditures		905.6	558
Gathering and Processing [Member] | Operating Segments [Member]
Other financial information [Abstract]
Total assets	[1]	11,713.9	10,908.5
Goodwill		46.6	256.6
Capital expenditures		417.8	273.2
Logistics and Marketing [Member] | Operating Segments [Member]
Other financial information [Abstract]
Total assets	[1]	5,644.9	3,595.1
Capital expenditures		470.9	251
Other [Member] | Operating Segments [Member]
Other financial information [Abstract]
Total assets	[1]	87.9	103
Corporate and Elimination [Member] | Operating Segments [Member]
Other financial information [Abstract]
Total assets	[1]	84.3	121.1
Capital expenditures		$ 16.9	$ 33.8
[1]	Assets in the Corporate and Eliminations column primarily include cash, prepaids and debt issuance costs for our TRP Revolver.

Segment Information, Revenues D

Segment Information, Revenues Disaggregated by Product and Service (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Revenue from External Customer [Line Items]
Revenue recognized from customer and non-customer		$ 1,964.7	$ 2,212.5
Non-customer revenue		11.8	(38.8)
Total revenues		2,299.4	2,455.6
Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Non-customer revenue		21.3	(28)
Not Designated as Hedging Instrument [Member]
Revenue from External Customer [Line Items]
Non-customer revenue	[1]	(9.5)	(10.8)
Natural Gas [Member]
Revenue from External Customer [Line Items]
Revenue recognized from customer and non-customer		411.3	470.1
NGL [Member]
Revenue from External Customer [Line Items]
Revenue recognized from customer and non-customer		1,408.1	1,607.3
Condensate And Crude Oil [Member]
Revenue from External Customer [Line Items]
Revenue recognized from customer and non-customer		137.7	86.9
Petroleum Products [Member]
Revenue from External Customer [Line Items]
Revenue recognized from customer and non-customer		7.6	48.2
Sales of Commodities [Member]
Revenue from External Customer [Line Items]
Total revenues		1,976.5	2,173.7
NGL Transportation and Services [Member]
Revenue from External Customer [Line Items]
Total revenues		36.2	41.1
Storage, Terminaling and Export [Member]
Revenue from External Customer [Line Items]
Total revenues		79.6	78.2
Gathering and Processing [Member]
Revenue from External Customer [Line Items]
Total revenues		194.5	152.1
Other [Member]
Revenue from External Customer [Line Items]
Total revenues		12.6	10.5
Fees from Midstream Services [Member]
Revenue from External Customer [Line Items]
Total revenues		$ 322.9	$ 281.9
[1]	Represents derivative activities that are not designated as hedging instruments under ASC 815.

Segment Information, Reconcilia

Segment Information, Reconciliation of Reportable Segment Operating Margin to Income (Loss) Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reconciliation of reportable segment operating margin to income (loss) before income taxes:
Operating margin	$ 383.2	$ 341.4
Depreciation and amortization expense	(237.4)	(198.1)
General and administrative expense	(77.7)	(52.6)
Interest income (expense), net	(75.4)	20.2
Change in contingent considerations	(9.7)	(56.1)
Other, net	(2)	1.2
Income (loss) before income taxes	(19)	56
Gathering and Processing [Member]
Reconciliation of reportable segment operating margin to income (loss) before income taxes:
Operating margin	229	220.8
Logistics and Marketing [Member]
Reconciliation of reportable segment operating margin to income (loss) before income taxes:
Operating margin	152.1	138.4
Other [Member]
Reconciliation of reportable segment operating margin to income (loss) before income taxes:
Operating margin	$ 2.1	$ (17.8)