Quarterly report pursuant to Section 13 or 15(d)

FAIR VALUE - Narrative (Details)

v3.21.2
FAIR VALUE - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
6 Months Ended
Apr. 01, 2021
Jun. 30, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Asset retirement obligations incurred and acquired   $ 8.0
Reliance    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Common stock, equity interest issued (in shares) 3,250,000  
Common stock, equity interest issued and issuable, exercise price (in dollars per share) $ 14.00  
Unsecured Notes due 2028 | Estimated Fair Value | Unsecured Debt    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair value of long-term debt   $ 595.4