CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (UNAUDITED) - USD ($) $ in Millions	Total	Non-controlling Interests	Common Units Partners' Capital General Public	Common Units Partners' Capital BP Holdco	Subordinated Units Partners' Capital BP Holdco	General Partner
Beginning Balance at Dec. 31, 2018	$ 210.9	$ 141.0	$ 836.8	$ (61.7)	$ (705.2)	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	133.2
Ending Balance at Sep. 30, 2019	229.5	138.1	846.4	(60.8)	(694.9)	0.7
Beginning Balance at Dec. 31, 2019	240.2	$ 136.9	$ 851.6	$ (60.3)	$ (689.2)	$ 1.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	142.6
Ending Balance at Sep. 30, 2020	$ 253.0