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Stock-based Compensation Plans (Narrative) (Details) $ / shares in Units, $ in Millions			3 Months Ended				9 Months Ended
	Jan. 27, 2021	Dec. 02, 2020	Jun. 30, 2021 USD ($) $ / shares shares	Mar. 31, 2021 $ / shares shares	Dec. 31, 2020 $ / shares shares	Jun. 30, 2020 USD ($) shares	Jun. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) shares
Share-based Payment Arrangement, Expense | $			$ 3.4			$ 1.8	$ 8.4	$ 5.0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $			$ 11.5				$ 11.5
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			131,178			474,423	566,666	274,009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares			0				108,950
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other than Option, Nonvested, Intrinsic Value | $ / shares			$ 14.42				$ 14.42
Share-based compensation liability | $			$ 2.7				$ 2.7
Granted, shares			3,567	1,254	180,987
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			$ 14.29	$ 11.94	$ 11.86
Granted, shares			3,567	1,254	180,987
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period							103,058
Share-based compensation, units awarded but not yet granted			199,994				199,994
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period			2,324				221,873
Granted, shares			7,127	82,565	129,081
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			$ 13.32	$ 12.81	$ 11.86
Granted, shares			7,127	82,565	129,081
Market Based Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.84%	1.77%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.16%	0.21%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	2 years 8 months 1 day	2 years 9 months 29 days
Granted, shares				4,187	234,199
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	1.84%	1.77%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares				$ 14.26	$ 15.39
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.16%	0.21%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	2 years 8 months 1 day	2 years 9 months 29 days
Granted, shares				4,187	234,199
Equity Option
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			2.01%	2.01%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.66%	0.66%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			6 years	6 years
Granted, shares				8,115	423,405
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			2.01%	2.01%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares				$ 3.08	$ 3.05
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.66%	0.66%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			6 years	6 years
Granted, shares				8,115	423,405
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					60,019
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					$ 11.86
Granted, shares					60,019
Share-based Payment Arrangement, Tranche Three [Member] | Performance Shares [Member]
Granted, shares					84,483
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					$ 11.86
Granted, shares					84,483

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