QUARTERLY FINANCIAL INFORMATION (unaudited) - Additional information (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2020	Jul. 31, 2019	Apr. 30, 2019	Oct. 31, 2018
QUARTERLY FINANCIAL INFORMATION (unaudited)
Loss on the TeesREP Biomass Power Plant project by APC	$ 2.6	$ 3.4	$ 27.6
Adjustment for research and development tax credit				$ 16.5

The favorable adjustment recorded to recognize research and development tax credits in net income.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration