Debt - FV, Maturities, etc. (Details) $ in Billions	9 Months Ended
Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Long term debt value
Leverage ratio, maximum	5.0
Leverage ratio, subsequent period	4.5
Level 2
Long term debt value
Fair value of the long-term debt	$ 8.9	$ 8.3

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

No definition available.

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant