Investment in Unconsolidated Ventures - Summarized Income Statement Information (Detail) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Revenues	$ 2.0	$ 1.8
Earnings (loss)	1.4	1.4
Equity in earnings of unconsolidated ventures	$ 0.5	$ 0.6

Amount of income (loss) from continuing operations reported by an equity method investee.

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Amount of revenue from sale of product and rendering of service reported by equity method investee.

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