Acquisitions - Consolidated Balance Sheet (Parenthetical) (Detail) - shares	Dec. 31, 2019	Dec. 31, 2018
Common Unitholders - Public
Business Acquisition [Line Items]
Common and subordinated units issued	0	17,014,377
Common and subordinated units outstanding	0	17,014,377
Common Unitholders - Affiliate
Business Acquisition [Line Items]
Common and subordinated units issued	0	10,282,654
Common and subordinated units outstanding	0	10,282,654
Subordinated Unitholders - Affiliate
Business Acquisition [Line Items]
Common and subordinated units issued	0	27,279,654
Common and subordinated units outstanding	0	27,279,654