v3.25.2
Fair Value Measurements - Breakdown by Fair Value Hierarchy Category for Financial Instruments (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value:    
Assets from commodity derivative contracts $ 28.7 $ 14.6
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Assets Assets
Liabilities from commodity derivative contracts $ 139.1 $ 140.7
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Liabilities, Current Liabilities, Current
Carrying Value [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value:    
Assets from commodity derivative contracts [1] $ 103.6 $ 87.0
Liabilities from commodity derivative contracts [1] 226.4 259.2
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Cash and cash equivalents 113.1 157.3
Carrying Value [Member] | TRGP Revolver and Commercial Paper Program [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 667.0  
Carrying Value [Member] | TRGP Senior Unsecured Notes [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 10,962.0 7,470.6
Carrying Value [Member] | Previous TRGP Revolver and Commercial Paper Program [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   1,130.5
Carrying Value [Member] | Securitization Facility [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   330.0
Fair Value [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value:    
Assets from commodity derivative contracts [1] 103.6 87.0
Liabilities from commodity derivative contracts [1] 226.4 259.2
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Cash and cash equivalents 113.1 157.3
Fair Value [Member] | Level 1 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value:    
Assets from commodity derivative contracts [1] 0.0 0.0
Liabilities from commodity derivative contracts [1] 0.0 0.0
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Cash and cash equivalents 0.0 0.0
Fair Value [Member] | Level 2 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value:    
Assets from commodity derivative contracts [1] 103.6 87.0
Liabilities from commodity derivative contracts [1] 225.3 259.2
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Cash and cash equivalents 0.0 0.0
Fair Value [Member] | Level 3 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Fair Value:    
Assets from commodity derivative contracts [1] 0.0 0.0
Liabilities from commodity derivative contracts [1] 1.1 0.0
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Cash and cash equivalents 0.0 0.0
Fair Value [Member] | TRGP Revolver and Commercial Paper Program [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 667.0  
Fair Value [Member] | TRGP Revolver and Commercial Paper Program [Member] | Level 1 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 0.0  
Fair Value [Member] | TRGP Revolver and Commercial Paper Program [Member] | Level 2 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 667.0  
Fair Value [Member] | TRGP Revolver and Commercial Paper Program [Member] | Level 3 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 0.0  
Fair Value [Member] | TRGP Senior Unsecured Notes [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 11,004.7 7,438.6
Fair Value [Member] | TRGP Senior Unsecured Notes [Member] | Level 1 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 0.0 0.0
Fair Value [Member] | TRGP Senior Unsecured Notes [Member] | Level 2 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 11,004.7 7,438.6
Fair Value [Member] | TRGP Senior Unsecured Notes [Member] | Level 3 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 0.0 0.0
Fair Value [Member] | Previous TRGP Revolver and Commercial Paper Program [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   1,130.5
Fair Value [Member] | Previous TRGP Revolver and Commercial Paper Program [Member] | Level 1 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   0.0
Fair Value [Member] | Previous TRGP Revolver and Commercial Paper Program [Member] | Level 2 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   1,130.5
Fair Value [Member] | Previous TRGP Revolver and Commercial Paper Program [Member] | Level 3 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   0.0
Fair Value [Member] | Securitization Facility [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   330.0
Fair Value [Member] | Securitization Facility [Member] | Level 1 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   0.0
Fair Value [Member] | Securitization Facility [Member] | Level 2 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   330.0
Fair Value [Member] | Securitization Facility [Member] | Level 3 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt   0.0
Senior Unsecured Notes [Member] | Carrying Value [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 5,034.4 5,034.4
Senior Unsecured Notes [Member] | Fair Value [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 4,986.5 4,928.0
Senior Unsecured Notes [Member] | Fair Value [Member] | Level 1 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 0.0 0.0
Senior Unsecured Notes [Member] | Fair Value [Member] | Level 2 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt 4,986.5 4,928.0
Senior Unsecured Notes [Member] | Fair Value [Member] | Level 3 [Member]    
Financial Instruments Recorded on Our Consolidated Balance Sheets at Carrying Value:    
Long-term debt $ 0.0 $ 0.0
[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 10 – 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.

 

Additional Information Regarding Level 3 Fair Value Measurements Included on Our Consolidated Balance Sheets

We report certain of our swaps at fair value using Level 3 inputs due to such derivative instruments 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 derivative instruments valued using indicative price quotations whose contract length extends into unobservable periods. The fair value of these swaps was determined using a discounted cash flow valuation technique based on a commodity forward curve, which is based on observable or public data sources and extrapolated when observable prices are not available. The significant unobservable inputs used in the fair value measurements of our Level 3 derivatives were the forward NGLs and natural gas pricing curves, for which a significant portion of the derivative instruments’ term is beyond available forward pricing.

 

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

 

 

 

 

Asset (Liability)

 

Balance, December 31, 2024

 

$

—

 

Unrealized gain (loss) included in OCI

 

 

(1.1

)

Balance, June 30, 2025

 

$

(1.1

)