Condensed Consolidated Balance Sheets (Parenthetical) - shares shares in Millions	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Preferred units issued (in shares)	4.7	4.7
Preferred units outstanding (in shares)	4.7	4.7
Common units issued (in shares)	65.5	65.5
Common units outstanding (in shares)	65.5	65.5