Consolidated Statement of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities:
Net income	$ 1,000.7	$ 445.3
Adjustments to arrive at cash provided by operating activities:
Depreciation	60.2	60.2
Amortization of intangible assets	29.7	24.0
Change in fair value of investments	(581.3)	73.8
Share-based compensation expense	24.4	22.4
Retirement benefit expense	60.1	63.4
Pension contributions	(18.7)	(17.3)
Net loss (gain) on disposition of property	0.2	(1.2)
Changes in assets and liabilities, excluding effects of acquisitions and foreign currency adjustments:
Receivables	(185.8)	(134.2)
Inventories	(88.4)	(12.1)
Accounts payable	119.1	50.9
Contract liabilities	63.6	52.4
Compensation and benefits	62.6	(99.1)
Income taxes	33.3	(79.2)
Other assets and liabilities	15.7	(0.8)
Cash provided by operating activities	595.4	448.5
Investing activities:
Capital expenditures	(52.1)	(56.6)
Acquisition of businesses, net of cash acquired	(283.0)	(259.3)
Purchases of investments	(0.2)	(2.6)
Proceeds from maturities of investments	0.2	5.4
Proceeds from sale of investments	0.0	37.9
Proceeds from sale of property	0.2	1.6
Payments for (Proceeds from) Other Investing Activities	(1.8)	0.0
Cash used for investing activities	(336.7)	(273.6)
Financing activities:
Net issuance of short-term debt		81.5
Issuance of short-term debt, net of issuance costs	1.4	0.0
Repayments of Short-term Debt	(0.4)
Repayment of long-term debt	0.0	(300.0)
Cash dividends	(248.7)	(236.3)
Purchases of treasury stock	(176.9)	(213.7)
Proceeds from the exercise of stock options	97.0	133.7
Other financing activities	(11.5)	0.8
Cash used for financing activities	(339.1)	(534.0)
Effect of exchange rate changes on cash	17.7	(17.5)
Decrease in cash, cash equivalents, and restricted cash	(62.7)	(376.6)
Cash, cash equivalents, and restricted cash at beginning of period	730.4	1,018.4
Cash, cash equivalents, and restricted cash at end of period	667.7	641.8
Components of cash, cash equivalents, and restricted cash
Total cash, cash equivalents, and restricted cash	$ 667.7	$ 641.8