Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating activities:
Net income	$ 590.4	$ 315.4
Adjustments to arrive at cash provided by operating activities:
Depreciation	29.9	30.2
Amortization of intangible assets	14.1	11.7
Change in fair value of investments	(390.4)	(71.0)
Share-based compensation expense	11.5	11.5
Retirement benefit expense	30.0	31.8
Pension contributions	(8.8)	(7.1)
Net loss on disposition of property	0.1	0.0
Changes in assets and liabilities, excluding effects of acquisitions and foreign currency adjustments:
Receivables	(85.5)	(85.0)
Inventories	(40.3)	1.7
Accounts payable	20.9	(0.4)
Contract liabilities	51.4	37.3
Compensation and benefits	7.3	(38.6)
Income taxes	72.8	(17.3)
Other assets and liabilities	43.1	10.9
Cash provided by operating activities	346.5	231.1
Investing activities:
Capital expenditures	(27.1)	(37.0)
Acquisition of businesses, net of cash acquired	(283.1)	(238.5)
Purchases of investments	0.0	(1.0)
Proceeds from maturities of investments	0.0	5.4
Proceeds from sale of investments	0.0	37.9
Proceeds from sale of property	0.1	0.2
Cash used for investing activities	(310.1)	(233.0)
Financing activities:
Net issuance of short-term debt	125.9	23.5
Cash dividends	(124.3)	(117.9)
Purchases of treasury stock	(83.5)	(106.0)
Proceeds from the exercise of stock options	48.9	104.8
Other financing activities	(4.2)	0.0
Cash used for financing activities	(37.2)	(95.6)
Effect of exchange rate changes on cash	26.6	5.3
Increase (decrease) in cash, cash equivalents, and restricted cash	25.8	(92.2)
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	756.2	926.2
Components of cash, cash equivalents, and restricted cash
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Total	$ 756.2	$ 926.2