Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		12 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period		$ (46.3)
Other comprehensive income (loss) before reclassifications
Before tax amount		(111.2)	$ 65.5	$ 33.4
Tax benefit (expense)		(5.4)	(5.8)	2.2
After tax amount		(116.6)	59.7	35.6
Amounts reclassified from accumulated other comprehensive income		5.1	(3.3)	7.7
Total other comprehensive (loss) income, net of tax		(111.5)	56.4	43.3
Reclassifications of certain income tax effects	[1]			0.0
Balance at the end of the period		(155.6)	(46.3)
Total Attributable to Hillenbrand, Inc.
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period		(46.3)	(102.8)	(140.6)
Other comprehensive income (loss) before reclassifications
Before tax amount		(109.0)	65.6	33.9
Tax benefit (expense)		(5.4)	(5.8)	2.2
After tax amount		(114.4)	59.8	36.1
Amounts reclassified from accumulated other comprehensive income		5.1	(3.3)	7.7
Total other comprehensive (loss) income, net of tax		(109.3)	56.5	43.8
Reclassifications of certain income tax effects				(6.0)
Balance at the end of the period		(155.6)	(46.3)	(102.8)
Pension and Postretirement
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period		(49.2)	(69.6)	(62.3)
Other comprehensive income (loss) before reclassifications
Before tax amount		18.4	22.5	(8.5)
Tax benefit (expense)		(5.7)	(5.6)	2.0
After tax amount		12.7	16.9	(6.5)
Amounts reclassified from accumulated other comprehensive income		3.7	3.5	5.2
Total other comprehensive (loss) income, net of tax		16.4	20.4	(1.3)
Reclassifications of certain income tax effects				(6.0)
Balance at the end of the period		(32.8)	(49.2)	(69.6)
Currency Translation (1)
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period		13.1	(21.1)	(64.7)
Other comprehensive income (loss) before reclassifications
Before tax amount		(126.8)	42.2	43.6
Tax benefit (expense)		0.0	0.0	0.0
After tax amount		(126.8)	42.2	43.6
Amounts reclassified from accumulated other comprehensive income		0.0	(8.0)	0.0
Total other comprehensive (loss) income, net of tax		(126.8)	34.2	43.6
Reclassifications of certain income tax effects				0.0
Balance at the end of the period		(113.7)	13.1	(21.1)
Net Unrealized Gain (Loss) on Derivative Instruments
Changes in accumulated other comprehensive income (loss) by component
Balance at the beginning of the period		(10.2)	(12.1)	(13.6)
Other comprehensive income (loss) before reclassifications
Before tax amount		(0.6)	0.9	(1.2)
Tax benefit (expense)		0.3	(0.2)	0.2
After tax amount		(0.3)	0.7	(1.0)
Amounts reclassified from accumulated other comprehensive income		1.4	1.2	2.5
Total other comprehensive (loss) income, net of tax		1.1	1.9	1.5
Reclassifications of certain income tax effects				0.0
Balance at the end of the period		(9.1)	(10.2)	(12.1)
Noncontrolling Interests
Other comprehensive income (loss) before reclassifications
Before tax amount		(2.2)	(0.1)	(0.5)
Tax benefit (expense)			0.0	0.0
After tax amount		(2.2)	(0.1)	(0.5)
Amounts reclassified from accumulated other comprehensive income		0.0	0.0	0.0
Total other comprehensive (loss) income, net of tax		$ (2.2)	$ (0.1)	$ (0.5)

[1] Income tax effects were reclassified from accumulated other comprehensive loss to retained earnings due to the adoption of Accounting Standards Update (“ASU”) 2018-02 Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. See Note 11 for more information.