Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Note 12 - Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				21.00%
Effective Income Tax Rate Reconciliation, Percent, Total		194.00%	26.00%	52.00%	26.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent				5.00%	4.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent				3.00%
Effective Income Tax Rate Reconciliation, Disposition of Asset, Percent				23.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent, Total					1.00%
Income Taxes Paid, Net, Total				$ 129
Proceeds from Income Tax Refunds						$ 21
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total		$ 204		204
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total		$ 567		567
Forecast [Member]
Income Taxes Paid, Net, Total	$ 18
Quincy Divestiture [Member]
Income Taxes Paid, Net, Total				$ 72
Flint [Member] \| Forecast [Member]
Income Taxes Paid, Net, Total	$ 17