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Contingent Proceeds Receivable, Biodiesel Tax Credit

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Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of the required periodic payments applied to principal.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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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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Amount of increase (decrease) in loss contingency liability.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Discontinued Operations and Assets Held for Sale - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended			24 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Aug. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Continuing operations	$ (691.3)	$ (145.3)	$ 25.4
Discontinued operations	0.0	20.0	12.2
Total cash proceeds	(691.3)	(125.3)	37.6
Proceeds from sale of business	0.0	110.8	0.0
Subsequent reduction of contingent litigation accrual related to July 2019 settlement	(5.7)	0.0
Income (loss) from discontinued operations, including gain (loss) on sale of discontinued operations	6.6	(10.9)	$ (8.6)
California Discontinued Entities - AltAir
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Continuing operations		55.5		$ 55.5
Discontinued operations		14.9		14.9
Total cash proceeds		70.4		70.4
Receivable for working capital settlement	(14.8)	14.8
Relief of existing liability for contingent litigation (net of immaterial rounding)	4.9			4.9
Net Contingent Proceeds Receivable related to re-enactment of 2018 BTC	5.7			5.7
Additional proceeds	8.1	14.8		22.9
Total expected proceeds	8.1	85.2		93.3
Initial loss on sale recognized in March 2018		41.4		41.4
Subsequent reduction of contingent litigation accrual related to July 2019 settlement	(2.4)	0.0		(2.4)
Subsequent accrual for contingent proceeds due upon re-enactment of the 2018 BTC	(5.7)	0.0		(5.7)
Income (loss) from discontinued operations, including gain (loss) on sale of discontinued operations	(8.1)	$ 41.4		$ 33.3
World Energy Note Receivable
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Promissory note					$ 12.3
Interest rate, stated percentage					6.00%
Periodic payment, principal	$ 0.5