Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
ASSETS
Allowance for bad debt	$ 0.3	$ 0.5
Property and equipment, accumulated depreciation	3,981.4	3,863.0
Intangible assets, accumulated amortization	$ 699.7	$ 668.8
Members’ equity:
Common units issued (in shares)	490,055,402	489,381,149
Common units outstanding (in shares)	489,381,149	490,055,402

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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