Company's Repurchase Activities (Parenthetical) (Detail) - Subsequent Event shares in Millions	Jan. 31, 2019 shares
Open Market Transactions
Capital Unit [Line Items]
Company's common units authorized for repurchase	1.7
Privately Negotiated Transactions
Capital Unit [Line Items]
Company's common units authorized for repurchase	2.5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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