Share-Based Compensation (Tables)

12 Months Ended

Sep. 30, 2020

Compensation Related Costs [Abstract]

Schedule of stock-based compensation costs

	Year Ended September 30,
	2020		2019		2018
Stock-based compensation cost	$	14.0	$	12.0	$	12.1
Less impact of income tax	3.2		2.8		2.9
Stock-based compensation cost, net of tax	$	10.8	$	9.2	$	9.2

Summary of assumptions used in determining fair value of options

The following assumptions were used in the determination of fair value:

	Year Ended September 30,
	2020		2019		2018
Risk-free interest rate	1.6	%	2.9	%	2.4	%
Weighted-average dividend yield	2.7	%	2.0	%	1.8	%
Weighted-average volatility factor	27.9	%	27.5	%	28.0	%
Expected life (years)	5.8		5.7		5.6

Summary of outstanding stock options

A summary of outstanding stock option awards as of September 30, 2020 and changes during the year is presented below:

	Number of Shares	Weighted-Average Exercise Price
Outstanding at September 30, 2019	2,137,604	$	35.43
Granted	454,929	31.94
Exercised	(58,618)	20.91
Forfeited	(45,255)	36.94
Expired/cancelled	(52,217)	39.93
Outstanding at September 30, 2020	2,436,443	$	35.00
Exercisable at September 30, 2020	1,621,923	$	33.93

Summary of outstanding restricted stock units

A summary of the non-vested stock awards, including dividends, as of September 30, 2020 (representing the maximum number of shares that could be vested) and changes during the year is presented below:

	Number of Shares	Weighted-Average Grant Date Fair Value
Time-Based Stock Awards
Non-vested time-based stock awards at September 30, 2019	68,930	$	41.19
Granted	338,105	31.21
Vested	(28,741)	38.15
Forfeited	(31,669)	32.99
Non-vested time-based stock awards at September 30, 2020	346,625	$	32.46

Summary of outstanding performance-based units

	Number of Shares	Weighted-Average Grant Date Fair Value
Performance-Based Stock Awards
Non-vested performance-based stock awards at September 30, 2019	520,145	$	46.41
Granted	429,782	33.58
Vested	(114,043)	53.29
Forfeited	(141,589)	50.05
Non-vested performance-based stock awards at September 30, 2020	694,295	$	36.59