Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash Flows from Operating Activities:
Net Earnings Including Redeemable Noncontrolling Interest	$ 44.2	$ 39.3
Adjustments to reconcile net earnings including redeemable noncontrolling interest to net cash provided by (used in) operating activities:
Depreciation and amortization	5.3	5.3
Non-cash stock-based compensation expense	3.5	1.5
Deferred income taxes	1.4	0.9
Other, net	(0.1)	(0.5)
Other changes in operating assets and liabilities:
Increase in receivables, net	(8.1)	(14.4)
Increase in inventories	(11.9)	(12.4)
Increase in prepaid expenses and other current assets	(2.9)	(4.8)
Decrease in other assets	0.4	0.5
Increase (decrease) in accounts payable and other current liabilities	4.5	(24.5)
Net Cash Provided by (Used in) Operating Activities	36.3	(9.1)
Cash Flows from Investing Activities:
Additions to property	(0.3)	(0.6)
Net Cash Used in Investing Activities	(0.3)	(0.6)
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt	55.0	0.0
Repayments of long-term debt	(40.0)	(90.1)
Purchases of treasury stock	(41.2)	(18.1)
Distributions to Post Holdings, Inc., net	0.0	(3.2)
Other, net	(2.2)	(1.1)
Net Cash Used in Financing Activities	(28.4)	(112.5)
Effect of Exchange Rate Changes on Cash and Cash Equivalents	0.5	0.0
Net Increase (Decrease) in Cash and Cash Equivalents	8.1	(122.2)
Cash and Cash Equivalents, Beginning of Year	35.8	152.6
Cash and Cash Equivalents, End of Period	$ 43.9	$ 30.4