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Stock-based Compensation Plans (Narrative) (Details) $ / shares in Units, $ in Millions		3 Months Ended			6 Months Ended
	Nov. 30, 2021	Mar. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 $ / shares shares	Mar. 31, 2021 shares	Mar. 31, 2022 USD ($) $ / shares shares
Share-based Payment Arrangement, Expense | $		$ 2.5
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $		$ 13.3			$ 13.3
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		944,631		664,082
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.70%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.76%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	2 years 9 months 29 days
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.70%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.76%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	2 years 9 months 29 days
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other than Option, Nonvested, Intrinsic Value | $ / shares		$ 12.92			$ 12.92
Share-based compensation liability | $		$ 2.1			$ 2.1
Granted, shares			199,549
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares			$ 13.64
Granted, shares			199,549
Performance Shares [Member]
Share-based compensation, units awarded but not yet granted		58,139			58,139
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		104,380
Granted, shares		88,250	135,129
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares		$ 13.03	$ 13.64
Granted, shares		88,250	135,129
Market Based Performance Shares
Granted, shares			230,089
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares			$ 15.76
Granted, shares			230,089
Equity Option
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.62%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.33%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 years
Granted, shares			457,482
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.62%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares			$ 3.43
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.33%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 years
Granted, shares			457,482
Minimum [Member] | Performance Shares [Member]
Performance Factors					0
Minimum [Member] | Market Based Performance Shares
Performance Factors					0
Maximum [Member] | Performance Shares [Member]
Performance Factors					2
Maximum [Member] | Market Based Performance Shares
Performance Factors					2
Share-based Payment Arrangement, Tranche Two [Member] | Performance Shares [Member]
Granted, shares			57,627
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares			$ 13.81
Granted, shares			57,627

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